# fun.explinear: A function to evaluate the exponential of a functional data... In Data2LD: Functional Data Analysis with Linear Differential Equations

## Description

Coefficient functions in linear differential systems are often required to be strictly positive. This can be achieved by defining the coefficient function to be the exponential of a functional data object, and using this as the user-defined coefficient function `fun\$fd` that evaluates the coefficient.

## Usage

 `1` ``` fun.explinear(tvec, bvec, Bbasisobj) ```

## Arguments

 `tvec` A vector of times at which the function is to be evaluated. `bvec` A vector or a single column of coefficient values for the functional data object. `Bbasisobj` A functional basis object.

## Details

The length of argument `bvec` must match the number of basis functions in argument `Bbasisobj`.

## Value

A numeric vector of the same length as that of argument `tvec` containing the exponentials of the values of the functional basis object.

## References

J. O. Ramsay and G. Hooker (2017) Dynamic Data Analysis. Springer.

`fun.explinear`
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