The simple binary maths window

This window allows you to add, subtract, divide and multiply two spectra. To use it just select a spectrum in the Left operand: list and a spectrum in the Right operand: list. Now select the operation you want to apply between them. A new spectrum called:

• Sum: (short name of left operand) + ( short name of right operand)
• Diff: (short name of left operand) - ( short name of right operand)
• Ratio: (short name of left operand) $\div$ ( short name of right operand)
• Product: (short name of left operand) x ( short name of right operand)

is created on the global list.

Note: the algorithm used to combine spectra that do not have the same wavelength positions is a simple interpolation. This does not preserve total flux, or errors, so this tool should only be used for quick qualitative arithmetic between real spectra. Artificial spectra (such as polynomial fits) do not have this restriction.

Accelerator keys

• Control-d Add the selected spectra from left and right.
• Control-s Subtract the selected spectra from left and right.
• Control-m Multiply the selected spectra from left and right.
• Control-i Divide the selected spectra from left and right.
• Control-w Close the window.
• F1 Display help on SPLAT-VO.
• Shift-F1 Display help on window.