2D and Circuit Selecting a Function

The value of a quantity being plotted depends upon its mathematical function, which you select on theTrace tab Function group box in the Reportwindow. The available, valid functions depend on the type of quantity (real or complex) that is being plotted. The function is applied to the quantity which is implicitly defined by all the swept and current variables. For example, "S(11)" is the value of the S-parameter for every swept combination of variables (e.g., "height", "frequency").

The following functions listed can be applied as Range Functions to previously specified Quantities and Functions using the Set Range Function window. Some of these functions can operate along an entire curve (min, max, integ, avg, rms, pk2pk, cang_deg, cang_rad). Their syntax is as follows:

cang_deg(quantity) implicitly implies derivative over the primary sweep
cang_deg(quantity, SweepVariable) explicitly means derivative over the sweep variable specified in the second argument (such as "Freq")

Note: For all range functions, the second parameter is assumed to be a sweep variable, and if it is not, the following error message results: “Second parameter to functions that apply to a range of values must be a sweep variable ”. You receive this message if you create a range function where the second parameter is a non-variable, such as deriv(dB(S₁₁),dB(S₁₂)). Whereas deriv(dB(S₁₁),F) is acceptable.

You can select on the following functions in the Trace tab Function group box:

abs	Absolute value
acos	Arc cosine
acosh	Hyperbolic arc cosine
ang_deg	Angle (phase) of a complex number, cut at +/-180
ang_deg_val	Angle (phase of a complex number in unitless degree values. Returns simple numbers.
ang_rad	Angle in radians
asin	Arc sine
asinh	Hyperbolic arc sine
atan	Arc tangent
atanh	Hyperbolic arc tangent
avg	Average of first parameter over the second parameter
avgabs	Absolute value of average.
cang_deg	Cumulative angle (phase) of the first parameter (a complex number) in degrees, along the second parameter (typically sweep variable). Returns a double precision value cut at +/-180.
cang_deg_val	Cumulative angle (phase) of the first parameter of the selected simulation quantity in unitless degree values. Returns simple numbers.
cang_rad	Cumulative angle of the first parameter in radians along a second parameter (typically a sweep variable) Returns a double precision value.
cmplx	Complex number with the first parameter as the real part and the second parameter as the imaginary part.
conjg	Conjugate of the complex number.
cos	Cosine
cosh	Hyperbolic cosine
crestfactor	Peak/RMS (root mean square) for the selected simulation quantity
dB(x)	20*log10(\|x\|)
dBm(x)	10*log10(\|x\|) +30
dBW(x)	10*log10(\|x\|)
db10normalize	10*log [normalize(mag(x))]
db20normalize	20*log [normalize(mag(x))]
deriv	Derivative of a given parameter.
even	Returns 1 if integer part of the number is even; returns 0 otherwise
exp	Exponential function (the natural anti-logarithm)
formfactor	Returns root mean square RMS/Mean Absolute Value for the selected simulation quantity.
iae	Returns the integral of the absolute deviation of the selected quantity from a target value that is entered via the additional argument. To use this function, you need to open the Add Trace Characteristics window and select the Error category.
im	Imaginary part of the complex number
int	Truncated integer function
integ	Integral of the selected quantity. Uses trapezoidal area.
integabs	Absolute value of integral.
ise	Returns the integral of the squared deviation of the selected quantity from a target value that is entered via an additional argument. To use this function, you need to open the Add Trace Characteristics window and select the Error category.
itae	Returns the time-weighted absolute deviation of the selected quantity from a target value that is entered via an additional argument. To use this function, you need to open the Add Trace Characteristics window and select the Error category.
itse	Returns the time-weighted squared deviation of the selected qty from a target value that is entered via an additional argument. To use this function, you need to open the Add Trace Characteristics window and select the Error category.
j0	Bessel function of the first kind (0^th order)
j1	Bessel function of the first kind (1^st order)
ln	Natural logarithm
log10	Logarithm base 10
lsidelobex	The ‘x’ value for the left side lobe: the next highest value to the left of the max value.
lsidelobey	The ‘y’ value for the left side lobe: the next highest value to the left of the max value.
mag	Magnitude of the complex number
max	Maximum of magnitudes.
max_swp	Maximum value of a sweep.
min	Minimum magnitudes.
min_swp	Minimum value of a sweep.
nint	Nearest integer
normalize	Divides each value within a trace by the maximum value of the trace. ex. normalize(mag(x))
odd	Returns 1 if integer part of the number is odd; returns 0 otherwise
overshoot	Obtains the peak overshoot over a point (double argument)
per	Calculates period.
pk2pk	Peak to peak. Difference between max and min of the first parameter over the second parameter. Returns the peak-to-peak value for the selected simulation quantity.
pkavg	Returns the ratio of the peak to peak-to-average for the selected quantity.
pmax	Period max.
pmin	Period minimum
prms	Period Root Mean Square.
pulsefall9010	Pulse fall time of the selected simulation quantity according to the 90%-10% estimate.
pulsefront9010	Pulse front time of the selected simulation quantity according to the 10%-90% estimate.
pulsefront3090	Pulse front time of the selected simulation quantity according to the 30%-90% estimate.
pulsemax	Pulse maximum on the front and tail estimates for the selected simulation quantity.
pulsemaxtime	Time at which the maximum pulse value of the selected simulation quantity is reached.
pulsemin	Pulse minimum on the front and tail estimates for the selected simulation quantity.
pulsemintime	Time at which the minimum pulse value of the selected simulation quantity is reached.
pulsetail50	Pulse tail time of the selected simulation quantity on the virtual peak to 50%.
pulsewidth5050	Pulse width of the selected simulation quantity as measured on the 50% points on the pulse front and pulse tail.
PulseWidth Functions
pw_plus	Pulse width of first positive pulse
pw_plus_max	Max. Pulse width of input stream
pw_plus_min	Min. Pulse width of input stream
pw_plus_avg	Average of the positive pulse width input stream
pw_plus_rms	RMS of the positive pulse width input stream
pw_minus_max	Max. Pulse width of input stream
pw_minus_min	Min. Pulse width of input stream
pw_minus_avg	Average of the negative pulse width input stream
pw_minus_rms	RMS of the negative pulse width input stream
polar	Converts the complex number in rectangular to polar
re	Real part of the complex number
rect	Converts the complex number in polar to rectangular
rem	Fractional part
ripple	Returns the ripple factor (AC RMS/Mean) for the selected quantity.
rms	Returns total root mean square of the selected quantity.
rmsAC	Returns the AC RMS for the selected quantity.
rsidelobex	The ‘x’ value for the right side lobe: the next highest value to the right of the max value.
rsidelobey	The ‘y’ value for the right side lobe: the next highest value to the right of the max value.
sgn	Sign extraction
sin	Sine
sinh	Hyperbolic sine
sqrt	Square root
tan	Tangent
tanh	Hyperbolic tangent
Undershoot	Obtains the peak undershoot over a point (double argument).
XAtYMax	Threshold crossing time: report first time (x value) at which an output quantity crosses YMax.
XAtYMin	Threshold crossing time: report first time (x value) at which an output quantity crosses a user definable threshold
xdb10beamdwidth	Width between left and right occurrences of values ‘x’ db10 from max. Takes 'x' as argument (3.0 default). To use this function, you need to open the Add Trace Characteristics window and select the Radiation category.
xdb20beamwidth	Width between left and right occurrences of values ‘x’ db20 from max. Takes 'x' as argument (3.0 default) To use this function, you need to open the Add Trace Characteristics window and select the Radiation category.
y0	Bessel function of the second kind (0^th order)
y1	Bessel function of the second kind (1^st order)

Note: Remember that the evaluated value of an expression is always interpreted in SI units. However, when an angle quantity is plotted in a report, you have the option to plot values in units other than SI. If you want to plot the polar angle of a complex simulation result, S₁₁ say, choose between ang_deg(S₁₁) and ang_rad(S₁₁). Both of these return the exact same angle quantity but in degree and radian units respectively.

Note that when used in expressions, some surprising outcomes might result. For example, the expression "1+ang_deg(S₁₁)" represents an ‘angle’ and the number "1" is treated as "1 rad". The angle SI unit is attached to any unitless number that is added/subtracted from an angle value. If you want to treat "1" as degrees, make it explicit and use "1deg + ang_deg(S₁₁)" instead.

If you are interested in unitless degree values, two additional functions exist: ang_deg_val(S₁₁) and cang_deg_val(S₁₁). These return simple numbers and are treated so by any expression. If the complex S₁₁ lies on the positive Y axis say, ang_deg_val(S₁₁) is 90 and "1 + ang_deg_val(S₁₁)" is 91.

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