plgcol0a: Returns 8-bit RGB values and double alpha transparency value for given color index from cmap0

`plgcol0a`: Returns 8-bit RGB values and double alpha transparency value for given color index from cmap0
Prev | Chapter 18. The Common API for PLplot | Next

#### `plgcol0a`: Returns 8-bit RGB values and double alpha transparency value for given color index from cmap0

`plgcol0a (` | icol0,
| r,
| g,
| b,
| alpha`)`;

Returns 8-bit RGB values (0-255) and double alpha transparency value (0.0 - 1.0) for given color from cmap0 (see the section called “Color Map0”). Values are negative if an invalid color id is given.

`icol0` (`PLINT`, input)

  Index of desired cmap0 color.

`r` (`PLINT *`, output)

  Pointer to 8-bit red value.

`g` (`PLINT *`, output)

  Pointer to 8-bit green value.

`b` (`PLINT *`, output)

  Pointer to 8-bit blue value.

`alpha` (`PLFLT *`, output)

  Pointer to PLFLT alpha transparency value.

This function is used in example 30.

Prev | Up | Next
`plgcol0`: Returns 8-bit RGB values for given color index from cmap0 | Home | `plgcolbg`: Returns the background color (cmap0[0]) by 8-bit RGB value