5020
How do I draw Legend graphic samples that show only 1 symbol instead of 3?
QUESTION:
How do I draw Legend graphic samples that show only 1 symbol instead of 3?
ANSWER:
By default, the Legend function graphic displays samples containing symbols using 3 symbols.
To create Legend samples that only display 1 symbol, you can position the symbols to overlap by setting the property SAMPLE_WIDTH=0. For example:
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x = RANDOMU(seed, 100)
y = RANDOMU(seed, 100) * 2 - 1
p0 = SCATTERPLOT(x, y, $
SYM_COLOR='red', SYMBOL='o', $
SYM_SIZE=1, SYM_THICK=2, $
NAME='Random points', $
MARGIN=[.1,.1,.065,.18], $
CLIP=0)
x = FINDGEN(50)/49.0
p1 = PLOT(x, SIN(x * 360 * !DTOR), $
SYM_COLOR='blue', SYMBOL='star', $
SYM_SIZE=2, SYM_THICK=2, $
LINESTYLE=6, $ ; no plot line
NAME='Other points', $
CLIP=0, $
CURRENT=p0, /OVERPLOT)
; Legend with 3-symbol sample (default)
lgnd = LEGEND(TARGET=[p0, p1], $
HORIZONTAL_SPACING=.1, $ ; position nicely within legend box
POSITION=[.36,.96], /NORMAL, $ ; position of legend box
/AUTO_TEXT_COLOR)
; Legend with 1-symbol sample
lgnd_1_symbol = LEGEND(TARGET=[p0, p1], $
SAMPLE_WIDTH=0, $ ; make symbols overlap
HORIZONTAL_SPACING=.1, $ ; position nicely within legend box
POSITION=[.9,.96], /NORMAL, $ ; position of legend box
/AUTO_TEXT_COLOR)
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Reviewed for external by JU, KK 14-May-2015