Predefined Variables

The following variables are set for each pixel and may be changed in equations:

1. r red value of pixel
2. g green value of pixel
3. b blue value of pixel
4. i intensity value of pixel (integer)
5. x x coordinate
6. y y coordinate
7. v density value of pixel (0..1)
8. re FFT real (if image has been Fourier transformed)
9. im FFT imaginary (if image has been Fourier transformed)
10. w wavelet coefficient (if image has been Wavelet transformed)

The following variables are set for each pixel, but any changes are ignored, because their value is calculated from equations or data points entered by the user.

1. d calibrated value of pixel (based on user calibration)

The following constants are set once, before executing the math command. They can be changed if desired, but in some cases this would not make sense.

1. IMAGES The total no. of images present
2. XRES No. of horizontal pixels in the display
3. YRES No. of vertical pixels in the display
4. ULX Upper left x coordinate of selected area
5. ULY Upper left y coordinate of selected area
6. LRX Lower right x coordinate of selected area
7. LRY Lower right y coordinate of selected area
8. CI Current image number
9. BPP Bits/pixel of current image
10. FRAMES Total frames of current image
11. XSIZE Width in pixels of current image
12. YSIZE Height in pixels of current image
13. XPOS Position of current image (0,0=upper left)
14. YPOS Position of current image (0,0=upper left)
15. CF Currently-visible frame no. of current image
16. CALLOG0 Calibration of 1st (x) dimension, 0 = linear, 1 = logarithmic, 2 = polynomial, 3 = distance from 0,0.
17. CALLOG1 Calibration of 2nd (y) dimension, 0 = linear, 1 = logarithmic, 2 = polynomial, 3 = distance from 0,0.
18. CALDIMS No. of dimensions that are calibrated (0-2)
19. FFTSTATE Current Fourier-transform state of image (-1, 0, or 1)
20. FMIN Lowest FFT value or high-resolution wavelet coeff
21. FMAX Highest FFT value or high-resolution wavelet coeff
22. FFAC Conversion factor for FFT value or high-resolution wavelet coeff to pixel value
23. WAVELETSTATE Current Wavelet-transformed state of image ( -1, 0, or 1)
24. WMIN Lowest low-resolution wavelet coefficient
25. WMAX Highest low-resolution wavelet coefficient
26. WFAC Conversion factor for low-resolution wavelet coefficient value to pixel value
27. Q00 to Q09 Image calibration coefficients for first dimension
28. Q10 to Q19 Image calibration coefficients for 2nd dimension dimension
29. GRAINS The total no. of grains found in the most recent instance of grain counting.
30. SPOTS The total no. of spots found in the most recent instance of grain counting (same as GRAINS).
31. PIXELS The total no. of pixels in the current image.
32. COMPENSATE The current setting of Pixel Density Calib. in the Spot or Strip Densitometry dialog. This determines the calibration method used when density values are accessed.
33. INVERT The current setting of Maximum Signal in the Spot or Strip Densitometry dialog. This determines whether the maximum signal is considered to be black or white when density values are accessed.

Example:

i=image[1][0][XSIZE-x-1][YSIZE-y-1];