# linearCombiner (1d, 2d, 3d)¶

Sum a user specified list of input nodalArrays, where each component can be scaled by a scalar factor and store the ouput in a single user-specifed nodalArray. All input and output data structures must have the same number of components.

The linearCombiner accepts the following parameters, in addition to those required by Updater:

## Data¶

in (string vector, required)
Input 1 to N are input nodalArrays to be summed. Each component can be scaled by a scalar factor.
out (string vector, required)
Output is a nodalArray which will contain the sum of the inputs.

## Parameters¶

coeffs (float vector, required)
A vector of n scalars, such that $$\mathrm{out} = \sum^{n-1}_{s=0} c_{s} \mathrm{in}_s$$

## Example¶

The following code block copies input nodalArray qnew to output nodalArray q:

<Updater copier>
kind = linCombinerUpdater
onGrid = domain

in = [qnew]
out = [q]

coeffs = [1.0]
</Updater>