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Goal: Guide you through creating and setting template attributes.

Before running the tutorial below, type "python" or "cdat" at the command line.  You will see the python prompt appear (i.e., ">>>"). You can now enter the command lines below.

You can view  or download  the full source code. To run the source code at the command line, type: "python template.py".

Definition of a Template

Picture templates (known as just "templates") describe how to display all objects on the VCS Canvas. 
More specifically, picture template attribute describe where segments of a picture will be displayed. 
Segments are graphics representations of: textual identification of the data; formatted values of single-valued 
dimensions and mean, maximum, and minimum data values; axes tick marks and labels; boxes and lines; a legend 
that is graphics method specific; and the data. 

# Import the modules needed for the tuturial
# cdms - Climate Data Management system accesses gridded data.
# vcs - Visualization and control System 1D and 2D plotting routines.
# cdutil - Climate utilitizes that contains miscellaneous routines for 
#          manipulating variables.
# time - This module provides various functions to mainpulate time values.
# os - Operation System routines for Mac, DOS, NT, or Posix depending on 
#      the system you're on.
# sys - This module provides access to some objects used or maintained by 
#       the interpreter and to functions that interact strongly with the interpreter.
import vcs, cdms, cdutil, time, os, sys

# Open data file:
filepath = os.path.join(sys.prefix, 'sample_data/clt.nc')
cdmsfile = cdms.open( filepath )

# Extract a 3 dimensional data set and get a subset of the time dimension
data = cdmsfile('clt', longitude=(-180, 180), latitude = (-90., 90.))

# Initial VCS:
v = vcs.init()

The VCS module contains a list of persistent template objects. To view this list issue the "show" command.

# Show the list of persistent templates.
v.show('template')
***********************Template Names List*************************
(   1):                 ASD                ASD1               ASD10
(   4):               ASD11               ASD12               ASD13   
(   7):               ASD14               ASD15           ASD1_of_2   
(  10):       ASD1_of_2_dud           ASD1_of_3       ASD1_of_3_dud   
(  13):           ASD1_of_4       ASD1_of_4_dud                ASD2   
(  16):           ASD2_of_2       ASD2_of_2_dud           ASD2_of_3   
(  19):       ASD2_of_3_dud           ASD2_of_4       ASD2_of_4_dud   
(  22):                ASD3           ASD3_of_3       ASD3_of_3_dud   
(  25):           ASD3_of_4       ASD3_of_4_dud                ASD4   
(  28):           ASD4_of_4       ASD4_of_4_dud                ASD5   
(  31):                ASD6                ASD7                ASD8   
(  34):                ASD9             ASD_dud             ASD_map   
(  37):         ASD_map1of2     ASD_map1of2_dud         ASD_map1of3   
(  40):     ASD_map1of3_dud         ASD_map1of4     ASD_map1of4_dud   
(  43):         ASD_map2of2     ASD_map2of2_dud         ASD_map2of3   
(  46):     ASD_map2of3_dud         ASD_map2of4     ASD_map2of4_dud   
(  49):         ASD_map3of3     ASD_map3of3_dud         ASD_map3of4   
(  52):     ASD_map3of4_dud         ASD_map4of4     ASD_map4of4_dud   
(  55):      BL_of6_1legend               BLof6      BR_of6_1legend   
(  58):               BRof6               LLof4           LLof4_dud   
(  61):               LRof4           LRof4_dud              ML_of6   
(  64):      ML_of6_1legend              MR_of6      MR_of6_1legend   
(  67):      UL_of6_1legend               ULof4           ULof4_dud   
(  70):               ULof6              UR_of6      UR_of6_1legend   
(  73):               URof4           URof4_dud        bold_bot_of3   
(  76):        bold_mid_of3        bold_top_of3       boldbot_of3_l   
(  79):       boldmid_of3_l       boldtop_of3_l             bot_of2   
(  82):             default         default_dud           hovmuller   
(  85):          mollweide2           no_legend          por_botof3   
(  88):      por_botof3_dud          por_midof3      por_midof3_dud   
(  91):          por_topof3      por_topof3_dud               quick   
(  94):             top_of2   
***********************End Template Names List*********************

# Assign the variable "t_asd" to the persistent 'ASD' template.
t_asd = v.gettemplate( 'ASD' )

# Create a new template from the existing 'ASD' template
t2_asd = v.createtemplate( 'new', 'ASD' )

# Plot the data using the above 'ASD' template.
v.plot( data, t_asd )

#############################################################################
# Show the many different ways to show the template members (attributes)
# and their values.
##############################################################################
t_asd.list()                    # list the templates members
t_asd.list('text')              # list only text members, same as t_asd.list('Pt')
t_asd.list('format')            # list only format members, same as t_asd.list('Pf')
t_asd.list('xtickmarks')        # list only xtickmarks members, same as t_asd.list('Pxt')
t_asd.list('ytickmarks')        # list only ytickmarks members, same as t_asd.list('Pyt')
t_asd.list('xlabels')           # list only xlabels members, same as t_asd.list('Pxl')
t_asd.list('ylabels')           # list only ylabels members, same as t_asd.list('Pyl')
t_asd.list('boxeslines')        # list only boxeslines members, same as t_asd.list('Pbl')
t_asd.list('legend')            # list only legend member, same as t_asd.list('Pls')
t_asd.list('data')              # list only data member, same as t_asd.list('Pds')
t_asd.list('file')              # list only file member and its values
t_asd.file.list()               # list only file member and its values
t_asd.list('mean')              # list only mean member and its values
t_asd.mean.list()               # list only mean member and its values

# Remove picture segments from the page.
t_asd.list( )
t_asd.xlabel2.priority = 0
t_asd.xtic2.priority = 0
t_asd.xtic2.priority = 0
t_asd.legend.priority=0

# save current 'Mean' placemant for x and y coordinates
xmean_current = t_asd.mean.x
ymean_current = t_asd.mean.y

# now change the placement
t_asd.mean.x=0.5       # move the "Mean" text to x-axis center
t_asd.mean.y=0.5       # move the "Mean" text to y-axis center

t_asd.data.priority = 0 # remove the data so the "Mean" text is visable.
v.update()

#############################################################################
# Place the colorbar legend vertically and to the right side.
#############################################################################
t_asd.data.priority = 1
t_asd.legend.priority = 1
t_asd.legend.list()         # list the legend members
v.mode=0                    # turn the automatic update off


# move 'Mean' text back where it was
t_asd.mean.x = xmean_current
t_asd.mean.y = ymean_current

# move the right side of a plot to the left to make space for the legend
# first move the inner plot
t_asd.data.x2 = 0.87
# then move the sorrounding box - the right y-axis
t_asd.box1.x2 = 0.87

# set the top x-axis (secind y axis) to be blank
t_asd.xlabel2.priority = 0
t_asd.xtic2.priority = 0
# set the right y-axis (second y axis) to be blank (priority=0)
t_asd.ylabel2.priority = 0
t_asd.ytic2.priority = 0

# move the colorbar legend position, to be vertial and to the right
t_asd.legend.x1=0.9
t_asd.legend.y1=0.82
t_asd.legend.x2=0.95
t_asd.legend.y2=0.3

# clear the canvas and plot the template again
v.clear()
v.plot( data, t_asd )

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