graph of 2 sine waves

[tony]

Can someone help me create a chart with 2 sine waves with the ability to
modify amplitude, frequency and phase angle.


thanks tony

 

[Laroche J]

tony wrote on 2008-04-26 22:37:

Can someone help me create a chart with 2 sine waves with the ability to
modify amplitude, frequency and phase angle.


thanks tony

First, name six ranges to hold twice the three variables: amplitude1,
frequency1, phase1, amplitude2, frequency2 and phase2.

Then fill a column range with the values 0 to 359 in increment of 1 (or more
or less if you like).

Enter the following formulas in the two cells to the right of your first
angle value (0°). I assume here that it is in cell A5, make changes
according to your needs.
in B5: =SIN((A5-phase1)*PI()/180*frequency1)*amplitude1
in C5: =SIN((A5-phase2)*PI()/180*frequency2)*amplitude2

Then select those two cells, grab the fill handle and drag down to the line
where you have your last angle entry.

Finally, select the three columns of data and make a line graph.

JL
Mac OS X 10.4.11, Office v.X 10.1.9

 

[Carl Witthoft]

tony wrote on 2008-04-26 22:37:


First, name six ranges to hold twice the three variables: amplitude1,
frequency1, phase1, amplitude2, frequency2 and phase2.

Then fill a column range with the values 0 to 359 in increment of 1 (or more
or less if you like).

Enter the following formulas in the two cells to the right of your first
angle value (0°). I assume here that it is in cell A5, make changes
according to your needs.
in B5: =SIN((A5-phase1)*PI()/180*frequency1)*amplitude1
in C5: =SIN((A5-phase2)*PI()/180*frequency2)*amplitude2

Then select those two cells, grab the fill handle and drag down to the line
where you have your last angle entry.

Finally, select the three columns of data and make a line graph.

NO NO NO!!! You must make a ScatterPlot, or things will go nuts in
short order.

JL
Mac OS X 10.4.11, Office v.X 10.1.9

I thought the OP was asking a deeper question, i.e. how to assign those
parameters to controls on the graph. In that case, he'll need to play
around a bit with the ActiveX toolbar or the Controls Toolbar.

 

[Laroche J]

Carl Witthoft wrote on 2008-04-28 17:09:

NO NO NO!!! You must make a ScatterPlot, or things will go nuts in
short order.

Not at all. In that case a scatter plot and a line graph will yield the same
result because the X values (the degrees) form a regular suite. I tried the
graph myself before posting my original answer, to make sure I give correct
advices.

JL
Mac OS X 10.4.11, Office v.X 10.1.9

 

[Carl Witthoft]

Carl Witthoft wrote on 2008-04-28 17:09:


Not at all. In that case a scatter plot and a line graph will yield the same
result because the X values (the degrees) form a regular suite. I tried the
graph myself before posting my original answer, to make sure I give correct
advices.

JL
Mac OS X 10.4.11, Office v.X 10.1.9

That only remains true so long as your x-data are, as you said, evenly
spaced. Sooner or later, you'll have some other spacing and forget what
sort of chart you've got :-( . Not to mention your options for setting
the X-axis scale are severely limited if you don't use ScatterPlot.