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sd.asapgrid.defineImage - Function

5.1.11 Define spatial grid
Description

Define spatial grid.

First two parameters, nx and ny, define number of pixels of the grid. If which of those is not specified, it will be set to the same value as the other. If none of them are specified, it will be determined from map extent and cell size.

Next two parameters, cellx and celly, define size of pixel. You should set those parameters as string, which is constructed numerical value and unit, e.g. ’0.5arcmin’, or numerical value. If those values are specified as numerical value, their units will be assumed to ’arcmin’. If which of those is not specified, it will be set to the same value as the other. If none of them are specified, it will be determined from map extent and number of pixels, or set to ’1arcmin’ if neither nx nor ny is set.

The last parameter, center, define the central coordinate of the grid. You should specify its value as a string, like,

’J2000 05h08m50s -16d23m30s’

or

’J2000 05:08:50 -16.23.30’

You can omit equinox when you specify center coordinate. In that case, J2000 is assumed. If center is not specified, it will be determined from the observed positions of input data.

Arguments





Inputs

nx

number of pixels along x (R.A.) direction

allowed:

int

Default:

-1

ny

number of pixels along y (Dec.) direction

allowed:

int

Default:

-1

cellx

size of pixel in x (R.A.) direction

allowed:

string, float

Default:

celly

size of pixel in y (Dec.) direction.

allowed:

string, float

Default:

center

central position of the grid

allowed:

string

Default:





Returns

Example


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