Math Operations¶
Note
< > = Required user input.
[ ] = Optional user input.
[PyDV]: = Python Data Visualizer command-line prompt.
abs¶
Take the absolute value of the y values of the curves. Modifies the existing curve.
[PyDV]: abs <curve-list>
absx¶
Take the absolute value of the x values of the curves. Modifies the existing curve.
[PyDV]: absx <curve-list>
average¶
Average the specified curvelist over the intersection of their domains.
[PyDV]: average <curve-list>
convolve¶
Computes the convolution of the two given curves. This is similar to the slower convolc method in ULTRA that uses direct integration and minimal interpolations. Shortcut: convol
[PyDV]: convolve <curve1> <curve2> [points]
convolveb¶
Computes the convolution of the two given curves and normalizing the second curve by the area under the curve. This computes the integrals directly which avoid padding and aliasing problems associated with FFT methods (it is however slower). Shortcut: convolb
[PyDV]: convolveb <curve1> <curve2> [points]
convolvec¶
Computes the convolution of the two given curves with no normalization. This computes the integrals directly which avoid padding and aliasing problems associated with FFT methods (it is however slower). Shortcut: convolb
[PyDV]: convolveb <curve1> <curve2> [points]
error-bar¶
Plot error bars on the given curve.
[PyDV]: errorbar <curve> <y-error-curve> <y+error-curve> [x-error-curve x+error-curve] [point-skip]
errorrange¶
Plot shaded error region on given curve, Shortcut: error-range
[PyDV]: errorrange <curve> <y-error-curve> <y+error-curve>
fft¶
Compute the one-dimensional discrete Fourier Transform for the y-values of the curves.
[PyDV]: fft <curve-list>
fftx¶
Compute the one-dimensional discrete Fourier Transform for the x-values of the curves.
[PyDV]: fftx <curve-list>
gaussian¶
Generate a gaussian function.
[PyDV]: gaussian <amplitude> <width> <center> [<# points> [<# half-widths>]]
L1¶
Makes new curve that is the L1 norm of two args; the L1 norm is integral( |curve1 - curve2| ) over the interval [xmin,xmax]. Also prints value of integral to command-line.
[PyDV]: L1 <curve1> <curve2> [<xmin> <xmax>]
L2¶
Makes new curve that is the L2 norm of two args; the L2 norm is integral( (curve1 - curve2)**2 )**(1/2) over the interval [xmin,xmax]. Also prints value of integral to command-line.
[PyDV]: L2 <curve1> <curve2> [<xmin> <xmax>]
log¶
Take the natural logarithm of the y values of the curves. If the optional argument keep-neg-vals is set to false, then zero and negative y-values will be discarded. keep-neg-vals is true by default. Shortcut: ln
[PyDV]: log <curve-list> [keep-neg-vals: True | False]
logx¶
Take the natural logarithm of the x values of the curves. If the optional argument keep-neg-vals is set to false, then zero and negative x-values will be discarded. keep-neg-vals is true by default. Shortcut: lnx
[PyDV]: logx <curve-list> [keep-neg-vals: True | False]
log10¶
Take the base 10 logarithm of the y values of the curves. If the optional argument keep-neg-vals is set to false, then zero and negative y-values will be discarded. keep-neg-vals is true by default.
[PyDV]: log10 <curve-list> [keep-neg-vals: True | False]
log10x¶
Take the base 10 logarithm of the x values of the curves. If the optional argument keep-neg-vals is set to false, then zero and negative y-values will be discarded. keep-neg-vals is true by default.
[PyDV]: log10x <curve-list> [keep-neg-vals: True | False]
makeintensive - 2.4.2¶
Set the y-values such that y[i] = y[i] / (x[i+1] - x[i]). Shortcut: mkint
[PyDV]: makeintensive <curve-list>
makeextensive - 2.4.2¶
Set the y-values such that y[i] = y[i] * (x[i+1] - x[i]). Shortcut: mkext
[PyDV]: makeextensive <curve-list>
norm¶
Makes a new curve that is the norm of two args. Also prints the value of the integral to command line.
[PyDV]: norm <curve> <curve> <p> <xmin> <xmax>
Note
The p-norm is (integral( (curve1 - curve2)**p )**(1/p) over the interval [xmin, xmax], where p = order.
powa¶
Raise a fixed value, a, to the power of the y values of the curves.
[PyDV]: powa <curve-list> <a>
powax¶
Raise a fixed value, a, to the power of the x values of the curves.
[PyDV]: powax <curve-list> <a>
xmax¶
Filter out points in curves whose x-values greater than limit
[PyDV]: xmax <curve-list> <limit>
y0¶
Take the zeroth order Bessel function of the second kind of the y values of the curves.
[PyDV]: y0 <curve-list>
y0x¶
Take the zeroth order Bessel function of the second kind of the x values of the curves.
[PyDV]: y0x <curve-list>
y1¶
Take the first order Bessel function of the second kind of the y values of the curves.
[PyDV]: y1 <curve-list>
y1x¶
Take the first order Bessel function of the second kind of the x values of the curves.
[PyDV]: y1x <curve-list>
ymax¶
Filter out points in curves whose y-values greater than limit
[PyDV]: ymax <curve-list> <limit>
yminmax¶
Trim the selected curves. Shortcut: ymm
[PyDV]: yminmax <curve-list> <low-limit> <high-lim>
yn¶
Take the nth order Bessel function of the second kind of y values of curves
[PyDV]: yn <curve-list> <n>
ynx¶
Take the nth order Bessel function of the second kind of x values of curves
[PyDV]: ynx <curve-list> <n>
diffMeasure¶
Compare two curves. For the given curves a fractional difference measure and its average is computed
[PyDV]: diffMeasure <curve1> <curve2> [tolerance]
fit¶
Make new curve that is polynomial fit to argument. n=1 by default, logy means take log(y-values) before fitting, logx means take log(x-values) before fitting
[PyDV]: fit <curve> [n] [logx] [logy]
integrate¶
Compute the definite integral of each curve in the list over the specified domain. Shortcut: int
[PyDV]: integrate <curve-list> [low-limit high-limit]
span¶
Generates a straight line of slope 1 and y intercept 0 in the specified domain with an optional number of points
[PyDV]: span <xmin> <xmax> [points]
vs¶
Plot the range of the first curve against the range of the second curve
[PyDV]: vs <curve1> <curve2>