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User Guide: Contents Page Index of Functions

| # Graphing Examples
## Graphing Sine & Cosine This screenshot shows the Chart & List Window being used to generate sine and cosine function plots. An integral calculation, between the range 2 to 5, is also shown for plot A. These plots can be generated using the input parameters below. See Graphing a Function for more information.
Input | Plot A: sin(x) Plot B: cos(x)
Range | 0; 2pi
Angle Mode | Radians
No. Points | 1000
Notes | Click the Calc button and then select Integral of Plot A to perform the integral calculation.
## Square Wave with Random Noise
Input | SIGN(sin(x)) + 0.2 * Ran - 0.1
Range | 0; 3
Angle Mode | Cycles
No. Points | 100
Notes | The SIGN function converts sine into a square wave, while Ran adds "noise". The noise will change each time you plot the function.
## Graphing an Asymptote
Input | 1 / x
Range | -10; +10
Angle Mode | N/A
Interval | 0.5
Notes | Use "Interval", not "No. Points" so as to create a discontinuity at x = 0 (i.e. 1 / 0 -> INFINITY).
## Equation of Time The "equation of time" approximates the difference between the apparent time and mean time (i.e. between solar noon and noon on the clock) throughout the year. The difference is due to a combination of the obliquity of the Earth's rotation axis and the eccentricity of its orbit.
Input | 9.87 * sin (2 * 360 * (x - 81) / 364) - 7.53 * cos (360 * (x - 81) / 364) - 1.5 * sin (360 * (x - 81) / 364)
Range | 1; 365
Angle Mode | Degrees
No. Points | 100
Notes |
## Creating a Polar Plot Below is the Polar Rose—a famous polar plot that looks like a petalled flower.
Input | 8 * sin(2.5t)
Range | 1; 4pi
Angle Mode | Radians
No. Points | 200
Notes | Enter the above equation and select: Axes->Polar Plot.
## Regression Analysis Below, a scatter plot of X-Y data with a line of best fit, as determined by cubic regression analysis.
Mode | Cubic Regression (X-Y)
Chart | X-Y Scatter Plot Select: Chart->X-Y Data Charts->Show Regression Fit to show best fit.
Notes | Import File: sample_xy_data.txt
## Histograms Below is a histogram generated using data in the DreamCalc SD Data List. The second chart shows a cumulative plot of the same data. The actual data values used to generate these plots can be found in the notes below.
Mode | Statistical Data (SD)
Chart | Histogram Select: Axes->Cumulative for the cumulative variation.
Notes | Import File: sample_histogram_data.txt
## Normal Q-Q Plots Professional Edition Only. A Normal Quantile-Quantile Plot generated using data in the DreamCalc SD Data List. The actual data values used to generate this plot can be found in the notes below.
Mode | Statistical Data (SD)
Chart | Normal Q-Q Plot (Professional Edition Only)
Notes | Import File: sample_qq_data.txt
## Cashflow Chart Professional Edition Only. The chart below shows cash amounts held in the cashflow list—a separate data list used in the financial calculations supported by the Professional Edition of DreamCalc.
Mode | Any - cashflow data is independent of other lists.
Chart | Cashflow
Cashflow | -2000, 3232, 7000, 9535, 13500, 21543, 12545, 18232, 11033, 7543, 5075
See also: Chart & List Window, and Graphing a Function |