Simple image plot data input

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Mon, 02/19/2018 - 06:43 am

Is there a place where I can find a simple step by step how-to input data for an image plot. I want to input time (x), size (y) and number concentration (z) per size and time. While I understood the extra line thing on x and y the z wave is always inputed as many waves and as expected is not used for the plot. I tried to copy and paste data from a file someone else did but in the end though everything looks fine, the plot is empty.

Why such an easy procedure as inputting data is so complicated for no reason?
I suspect the difficulty you're having is that Igor needs a 2D matrix of values for an image, and you have only a bunch of 1D waves.

If you're looking at your waves in a table it only *looks* like it is a 2D matrix.

That's why the Load General Text Waves dialog has a "load columns into matrix" option.

It also has a "load from clipboard" option.

I created a tiny matrix in a text file using Notepad (on the PC)

1 2 3 4
5 6 7 8
9 10 11 12


and copied the entire thing to the clipboard.

In Igor, instead of pasting it into a table, I chose Data->Load Waves...
I selected General Text from the popup, checked "Make table", "Load from clipboard", and "Load columns into Matrix"

A screenshot of the dialog is attached.

After clicking "Do It", the data was loaded as a 3x4 matrix:
•LoadWave/G/M/D/A=wave/E=1 "Clipboard"
  General text load from "Clipboard"
  Matrix size: (3,4), wave: wave0


A screenshot of the table is attached.

The matrix is displayed as an image with the simple command:

newimage wave0


You can use X and Y scaling on the matrix to set the axis ranges.

Using X and Y waves to assign pixel boundaries is unusual (but supported); it is needed only when the x and y increments are not linear.

[If you post the data you're working with, we can help you more specifically.]

--Jim Prouty
Software Engineer, WaveMetrics, Inc.
LoadAsMatrix.png MatrixInTable.png TimyImage.png

February 19, 2018 at 08:50 am - Permalink