Discussion :

[xcchaossx]

Bonjour à tous,
J'aimerais utiliser Matlab pour extraire un tableau de mes températures en fonction du temps (plus précisément température journalière).
Pour cela je dispose d'un gros fichier netcdf MARS3D multidimensions, multivariable.
J'aimerais obtenir en sortie soit un tableau des températures journalières, soit un graphe (l'essentiel est de pouvoir tirer cette information du fichier source .nc).
Mes étapes seraient :
1/comment à partir d'un fichier source je peux extraire des variables d’intérêt avec Matlab pour réécrire un fichier "épuré"
2/comment à partir de ce fichier je peux produire un tableau de ma variable exprimée en fonction du temps (exemple température journalière chaque jour pour mon fichier mensuel).

La variable qui m'intéresse est la température "TEMP", la latitude, la longitude et le temps.

Voici ci-dessous les infos concernant mon fichier source, merci par avance pour votre aide !

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Filename: 'C:\Users...\champs_meno_BE201704.nc'
          Name: '/'
    Dimensions: [1×10 struct]
     Variables: [1×31 struct]
    Attributes: [1×57 struct]
        Groups: []
        Format: 'netcdf4_classic'

Code :

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ncdisp('champs_meno_BE201704.nc')
Source:
           C:\Users\...\champs_meno_BE201704.nc
Format:
           netcdf4_classic
Global Attributes:
           limi                     = 0
           lima                     = 1100
           pasi                     = 1
           ljmi                     = 0
           ljma                     = 462
           pasj                     = 1
           lkmi                     = 1
           lkma                     = 60
           pask                     = 1
           global_imin              = 0
           global_imax              = 1100
           global_jmin              = 0
           global_jmax              = 462
           data_type                = 'OCO oriented grid'
           format_version           = '1.3.1'
           Conventions              = 'CF-1.6 OCO-1.3.1 COMODO-1.0'
           netcdf_version           = '4.1.2'
           product_version          = '1.0'
           references               = 'http://www.previmer.org/'
           easting                  = 'longitude'
           northing                 = 'latitude'
           grid_projection          = 'n/a'
           distribution_statement   = 'Data restrictions: for registered users only'
           institution              = 'IFREMER'
           institution_references   = 'http://www.ifremer.fr/'
           data_centre              = 'IFREMER OCO DATA CENTER'
           data_centre_references   = 'http://www.previmer.org/'
           title                    = 'PREVIMER MENOR 1200 forecast'
           creation_date            = '2017-04-04T21:09:49Z'
           run_time                 = '2017-04-04T21:09:49Z'
           history                  = .../champs_meno_BE201704.nc
                                      2017-04-04T21:09:49Z: creation'
           model_name               = 'MARS'
           arakawa_grid_type        = 'C1'
           source                   = 'MARS3D V10.10'
           area                     = 'North Western Mediterranean Sea'
           southernmost_latitude    = '39.5000'
           northernmost_latitude    = '44.5000'
           latitude_resolution      = '1.082250000000000E-002'
           westernmost_longitude    = '0.0000'
           easternmost_longitude    = '15.9999'
           longitude_resolution     = '1.454540000000000E-002'
           minimum_depth            = '5.000000'
           maximum_depth            = '3500.000'
           depth_resolution         = 'n/a'
           forecast_range           = '4-days forecast'
           forecast_type            = 'forecast'
           operational_status       = 'experimental'
           NCO                      = '"4.6.4"'
           start_date               = '2017-04-01T00:00:00Z'
           stop_date                = '2017-04-01T00:00:00Z'
           software_version         = 'PREVIMER forecasting system v2'
           product_name             = 'PREVIMER_F2-MARS3D-MENOR1200_20170401T0000Z.nc'
           field_type               = '3-hourly'
           comment                  = 'Use of Meteo-France ARPEGEHR meteorological data'
           contact                  = 'cdoco-exploit@ifremer.fr'
           quality_index            = '0'
           nco_openmp_thread_number = 1
Dimensions:
           ni    = 1101
           nj    = 463
           ni_u  = 1101
           nj_u  = 463
           ni_v  = 1101
           nj_v  = 463
           ni_f  = 1101
           nj_f  = 463
           time  = 240   (UNLIMITED)
           level = 60
Variables:
    ni         
           Size:       1101x1
           Dimensions: ni
           Datatype:   single
           Attributes:
                       long_name            = 'x-dimension of the grid'
                       standard_name        = 'x_grid_index'
                       c_grid_axis_shift    = 0
                       axis                 = 'X'
                       c_grid_dynamic_range = '4:1088'
    nj         
           Size:       463x1
           Dimensions: nj
           Datatype:   single
           Attributes:
                       long_name            = 'y-dimension of the grid'
                       standard_name        = 'y_grid_index'
                       axis                 = 'Y'
                       c_grid_axis_shift    = 0
                       c_grid_dynamic_range = '3:456'
    ni_u       
           Size:       1101x1
           Dimensions: ni_u
           Datatype:   single
           Attributes:
                       long_name            = 'x-dimension of the grid at u location'
                       standard_name        = 'x_grid_index_at_u_location'
                       c_grid_axis_shift    = 0.5
                       axis                 = 'X'
                       c_grid_dynamic_range = '4:1087'
    nj_u       
           Size:       463x1
           Dimensions: nj_u
           Datatype:   single
           Attributes:
                       long_name            = 'y-dimension of the grid at u location'
                       standard_name        = 'y_grid_index_at_u_location'
                       axis                 = 'Y'
                       c_grid_axis_shift    = 0
                       c_grid_dynamic_range = '3:456'
    ni_v       
           Size:       1101x1
           Dimensions: ni_v
           Datatype:   single
           Attributes:
                       long_name            = 'x-dimension of the grid at v location'
                       standard_name        = 'x_grid_index_at_v_location'
                       c_grid_axis_shift    = 0
                       axis                 = 'X'
                       c_grid_dynamic_range = '4:1088'
    nj_v       
           Size:       463x1
           Dimensions: nj_v
           Datatype:   single
           Attributes:
                       long_name            = 'y-dimension of the grid at v location'
                       standard_name        = 'y_grid_index_at_v_location'
                       axis                 = 'Y'
                       c_grid_axis_shift    = 0.5
                       c_grid_dynamic_range = '2:455'
    ni_f       
           Size:       1101x1
           Dimensions: ni_f
           Datatype:   single
           Attributes:
                       long_name            = 'x-dimension of the grid at f location'
                       standard_name        = 'x_grid_index_at_f_location'
                       c_grid_axis_shift    = 0.5
                       axis                 = 'X'
                       c_grid_dynamic_range = '4:1087'
    nj_f       
           Size:       463x1
           Dimensions: nj_f
           Datatype:   single
           Attributes:
                       long_name            = 'y-dimension of the grid at f location'
                       standard_name        = 'y_grid_index_at_f_location'
                       axis                 = 'Y'
                       c_grid_axis_shift    = 0.5
                       c_grid_dynamic_range = '2:455'
    latitude   
           Size:       1101x463
           Dimensions: ni,nj
           Datatype:   double
           Attributes:
                       long_name     = 'latitude'
                       standard_name = 'latitude'
                       units         = 'degrees_north'
                       _FillValue    = 1.7e+38
                       valid_min     = -90
                       valid_max     = 90
    longitude  
           Size:       1101x463
           Dimensions: ni,nj
           Datatype:   double
           Attributes:
                       long_name     = 'longitude'
                       standard_name = 'longitude'
                       units         = 'degrees_east'
                       _FillValue    = 1.7e+38
                       valid_min     = -180
                       valid_max     = 180
    time       
           Size:       240x1
           Dimensions: time
           Datatype:   double
           Attributes:
                       long_name     = 'time in seconds (UT)'
                       standard_name = 'time'
                       units         = 'seconds since 1900-01-01T00:00:00Z'
                       axis          = 'T'
                       time_origin   = '01-JAN-1900 00:00:00'
                       conventions   = 'relative number of seconds with no decimal part'
    level      
           Size:       60x1
           Dimensions: level
           Datatype:   single
           Attributes:
                       long_name          = 'sigma level'
                       axis               = 'Z'
                       c_grid_axis_shift  = 0
                       positive           = 'up'
                       valid_min          = -1
                       valid_max          = 0
                       standard_name      = 'ocean_s_coordinate'
                       formula_terms      = 's: level eta: XE depth: H0 a: theta b: b depth_c: hc'
                       formula_definition = 'z(n,k,j,i) = eta(n,j,i)*(1+s(k)) + depth_c*s(k) + (depth(j,i)-depth_c)*C(k)'
    longitude_u
           Size:       1101x463
           Dimensions: ni_u,nj_u
           Datatype:   int16
           Attributes:
                       long_name     = 'longitude at u location'
                       standard_name = 'longitude_at_u_location'
                       units         = 'degrees_east'
                       scale_factor  = 0.0002472
                       add_offset    = 8
                       valid_min     = -32767
                       valid_max     = 32767
                       _FillValue    = -32768
    longitude_v
           Size:       1101x463
           Dimensions: ni_v,nj_v
           Datatype:   int16
           Attributes:
                       long_name     = 'longitude at v location'
                       standard_name = 'longitude_at_v_location'
                       units         = 'degrees_east'
                       scale_factor  = 0.0002472
                       add_offset    = 8
                       valid_min     = -32767
                       valid_max     = 32767
                       _FillValue    = -32768
    latitude_u 
           Size:       1101x463
           Dimensions: ni_u,nj_u
           Datatype:   int16
           Attributes:
                       long_name     = 'latitude at u location'
                       standard_name = 'latitude_at_u_location'
                       units         = 'degrees_north'
                       scale_factor  = 7.9348e-05
                       add_offset    = 42
                       valid_min     = -32767
                       valid_max     = 32767
                       _FillValue    = -32768
    latitude_v 
           Size:       1101x463
           Dimensions: ni_v,nj_v
           Datatype:   int16
           Attributes:
                       long_name     = 'latitude at v location'
                       standard_name = 'latitude_at_v_location'
                       units         = 'degrees_north'
                       scale_factor  = 7.9348e-05
                       add_offset    = 42
                       valid_min     = -32767
                       valid_max     = 32767
                       _FillValue    = -32768
    SIG        
           Size:       60x1
           Dimensions: level
           Datatype:   single
           Attributes:
                       long_name     = 'sigma variable'
                       standard_name = 'ocean_s_variable'
                       units         = ''
                       valid_min     = -1
                       valid_max     = 0
                       _FillValue    = 999
    Csu_sig    
           Size:       60x1
           Dimensions: level
           Datatype:   single
           Attributes:
                       long_name          = 'C(s) law at mid layer'
                       standard_name      = 'ocean_s_coordinate_function_at_midlayer'
                       units              = ''
                       valid_min          = -2
                       valid_max          = 2
                       _FillValue         = 999
                       formula_definition = 'C(k) = (1-b)*sinh(a*s(k))/sinh(a) + b*[tanh(a*(s(k)+0.5))-tanh(0.5*a)]/(2*tanh(0.5*a))'
    hc         
           Size:       1101x463
           Dimensions: ni,nj
           Datatype:   int16
           Attributes:
                       long_name     = 'depth over which the resolution is increased'
                       standard_name = 'ocean_s_coordinate_thick_of_surface_resolution'
                       units         = 'm'
                       coordinates   = 'latitude longitude'
                       scale_factor  = 0.0079348
                       add_offset    = 240
                       valid_min     = -32767
                       valid_max     = 32767
                       _FillValue    = -32768
    b          
           Size:       1x1
           Dimensions: 
           Datatype:   single
           Attributes:
                       long_name     = 'bottom control parameter'
                       standard_name = 'ocean_s_coordinate_bottom_control'
                       units         = ''
                       valid_min     = 0
                       valid_max     = 1
                       _FillValue    = 999
    theta      
           Size:       1x1
           Dimensions: 
           Datatype:   single
           Attributes:
                       long_name     = 'surface control parameter'
                       standard_name = 'ocean_s_coordinate_surface_control'
                       units         = ''
                       valid_min     = 0
                       valid_max     = 20
                       _FillValue    = 999
    H0         
           Size:       1101x463
           Dimensions: ni,nj
           Datatype:   int16
           Attributes:
                       long_name     = 'bathymetry relative to the mean level'
                       standard_name = 'model_sea_floor_depth_below_geoid'
                       units         = 'm'
                       coordinates   = 'latitude longitude'
                       scale_factor  = 0.15336
                       add_offset    = 4975
                       valid_min     = -32767
                       valid_max     = 32767
                       _FillValue    = -32768
    HX         
           Size:       1101x463
           Dimensions: ni_u,nj_u
           Datatype:   int16
           Attributes:
                       long_name     = 'bathymetry at u-location relative to the mean level'
                       standard_name = 'model_sea_floor_depth_below_geoid_at_u_location'
                       units         = 'm'
                       coordinates   = 'latitude_u longitude_u'
                       scale_factor  = 0.15336
                       add_offset    = 4975
                       valid_min     = -32767
                       valid_max     = 32767
                       _FillValue    = -32768
    HY         
           Size:       1101x463
           Dimensions: ni_v,nj_v
           Datatype:   int16
           Attributes:
                       long_name     = 'bathymetry at v-location relative to the mean level'
                       standard_name = 'model_sea_floor_depth_below_geoid_at_v_location'
                       units         = 'm'
                       coordinates   = 'latitude_v longitude_v'
                       scale_factor  = 0.15336
                       add_offset    = 4975
                       valid_min     = -32767
                       valid_max     = 32767
                       _FillValue    = -32768
    XE         
           Size:       1101x463x240
           Dimensions: ni,nj,time
           Datatype:   int16
           Attributes:
                       long_name     = 'sea surface height'
                       standard_name = 'sea_surface_height_above_geoid'
                       units         = 'm'
                       coordinates   = 'latitude longitude'
                       scale_factor  = 0.0015259
                       add_offset    = 0
                       valid_min     = -32767
                       valid_max     = 32767
                       _FillValue    = -32768
    UZ         
           Size:       1101x463x60x240
           Dimensions: ni_u,nj_u,level,time
           Datatype:   int16
           Attributes:
                       long_name     = '3d zonal velocity'
                       standard_name = 'sea_water_x_velocity_at_u_location'
                       units         = 'm s-1'
                       coordinates   = 'latitude_u longitude_u'
                       scale_factor  = 0.00061037
                       add_offset    = 0
                       valid_min     = -32767
                       valid_max     = 32767
                       _FillValue    = -32768
    VZ         
           Size:       1101x463x60x240
           Dimensions: ni_v,nj_v,level,time
           Datatype:   int16
           Attributes:
                       long_name     = '3d meridional velocity'
                       standard_name = 'sea_water_y_velocity_at_v_location'
                       units         = 'm s-1'
                       coordinates   = 'latitude_v longitude_v'
                       scale_factor  = 0.00061037
                       add_offset    = 0
                       valid_min     = -32767
                       valid_max     = 32767
                       _FillValue    = -32768
    SAL        
           Size:       1101x463x60x240
           Dimensions: ni,nj,level,time
           Datatype:   int16
           Attributes:
                       long_name     = 'salinity'
                       standard_name = 'sea_water_salinity'
                       units         = '1e-3'
                       coordinates   = 'latitude longitude'
                       scale_factor  = 0.00083926
                       add_offset    = 22.5
                       valid_min     = -32767
                       valid_max     = 32767
                       _FillValue    = -32768
    TEMP       
           Size:       1101x463x60x240
           Dimensions: ni,nj,level,time
           Datatype:   int16
           Attributes:
                       long_name     = 'temperature'
                       standard_name = 'sea_water_potential_temperature'
                       units         = 'degrees_Celsius'
                       coordinates   = 'latitude longitude'
                       scale_factor  = 0.00083926
                       add_offset    = 22.5
                       valid_min     = -32767
                       valid_max     = 32767
                       _FillValue    = -32768
    TAUX       
           Size:       1101x463x240
           Dimensions: ni_u,nj_u,time
           Datatype:   int16
           Attributes:
                       long_name     = 'U-component of Surface Wind Stress'
                       standard_name = 'surface_downward_x_stress_at_u_location'
                       units         = 'N m-2'
                       coordinates   = 'latitude_u longitude_u'
                       scale_factor  = 0.0015259
                       add_offset    = 0
                       valid_min     = -32767
                       valid_max     = 32767
                       _FillValue    = -32768
    TAUY       
           Size:       1101x463x240
           Dimensions: ni_v,nj_v,time
           Datatype:   int16
           Attributes:
                       long_name     = 'V-component of Surface Wind Stress'
                       standard_name = 'surface_downward_y_stress_at_v_location'
                       units         = 'N m-2'
                       coordinates   = 'latitude_v longitude_v'
                       scale_factor  = 0.0015259
                       add_offset    = 0
                       valid_min     = -32767
                       valid_max     = 32767
                       _FillValue    = -32768

[le fab]

salut

tu peux peut être regarder du coté des datastore

[xcchaossx]

salut

tu peux peut être regarder du coté des datastore

Bonjour et merci pour ce conseil,
malheureusement j'ai regardé dans tous les types de datastore (https://fr.mathworks.com/help/matlab...datastore.html) et aucun ne fonctionne avec mon type de fichier netcdf.

Code :

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Error using xxxDatastore (line 137)
Input folders or files contain non-standard file extensions.
 
Use FileExtensions Name-Value pair to include the non-standard file extensions.

Si quelqu'un sur le forum a déjà été amené à manipuler des gros fichiers netcdf type model_name: MARS, arakawa_grid_type: C1 (gros parce que de nombreuses variables, doubles latitudes/longitudes), je suis preneuse de conseils.

Merci beaucoup !

[le fab]

et qu'a de particulier ce format ?