REAME file for directory rallpacks/theor.
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Contents
README : this file.
Makefile : for compilation of the currinj  file
.c files : source files for compilation.

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Currinj : Laplace transform solution for linear cables.

The currinj program iteratively calculates V(x,t);  the voltage on
the cable at point x and time t. It generates a time series of these
values in two data files : one for x=0 and the other for any specified
x. The output data file format is ascii, with one data point with the fields
time	value
on every line. Two files are generated, v0 for the current injection end
of the cable and vx for a point at distant x from this end. By default
vx corresponds to the far end of the cable.
The output times start at 0.0 and end at the specified T value (0.25 by
default).

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The solution is from "Electrical current flow in excitable cells",
OUP, 1983; Jack, Noble and Tsien, pp 79,80, also pp 68. This solution is
a sum of a series, and therefore its accuracy depends on the number of
terms used in the sum. The use 10 terms gives at least six figure accuracy
for a cable of electrotonic length 1.0. For length 0.08, six fig accuracy
may be obtained with 200 terms.

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The currinj options are :
-t tau0 	: Membrane time constant of cable = Rm * Cm
-T runTime	: Length of simulation.
-D dt		: Time step for output.
-v vrest	: Resting potential of cable.
-r RA		: Axial resistivity, Resistance * length units
-L lambda	: Length constant in length units.
-x dist		: Point on cable at which voltage is to be sampled,
				in length units.
-l length	: Length of cable, in length units.
-d dia		: diameter of cable, in length units.
-i inj		: injected current, in length units.
-n nterms	: Number of terms to use for the solution.	
-h help		: print a brief list of options.


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source files : The file inj.c is the main file which sets up and
	calculates the Laplace transform solution.
	The remaining files compute the error function erfc and
	are from Numerical Recipes in C, by Press et al. Users
	should take the responsibility for ensuring that they have
	fulfilled the copyright conditions for making copies of these
	files.

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compilation :
To compile the currinj program, just type 'make' in this directory.

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