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jstavitsky1-Visitor
1-Visitor
February 14, 2015
Question

Why is ln(x) not plotted below about -5?

  • February 14, 2015
  • 2 replies
  • 1848 views

Asking for calculated values returns accurate results, but the plot cuts off below approximately -4.6 with any zoom.

2 replies

R
RichardJ19-Tanzanite
19-Tanzanite
February 14, 2015

Please post a worksheet. There is no way to answer your question without a worksheet showing what you have done. You should not be able to plot ln(x) for any number less than or equal to zero. ln(0) is undefined, and ln(<0) is a complex number.

J
jstavitsky1-VisitorAuthor
1-Visitor
February 14, 2015

Mathcad 15, sorry I forgot to mention

R
RichardJ19-Tanzanite
19-Tanzanite
February 14, 2015

OK. Now I see what you mean. It's because you are using the Quickplot feature of Mathcad. It chooses the number of points to plot, and the location of those points. If you define x using a range variable you have more control.

V
24-Ruby IV
ValeryOchkov24-Ruby IV
24-Ruby IV
February 14, 2015

ln.png

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