How do i leave out part of a sinus curve? How do i write it if, i were supposed to leave out the first 45° of this. I have MathCad 14.
You may define you function either by using the if-statement (Programming palette) or the if() function. Set the function to zero for values of t smaller than pi/4 or set it to NaN if you don't want to see anything in that range.
Is making the function periodic of interest?
WE
I'm not sure I understand it. Is there anything I should do different in the one i have done? Or should i do it all in another way? I can't find Programming palette.
EDIT: Couldn't see the added files before. I think i understand it now. Thanks a lot 
Tommi Lauridsen wrote:
I can't find Programming palette.
If there aren't any additional question you may consider closing this thread-
WE
Hi Tommi Lauridsen! I think I have the answer to your problem. Open the attached file with Mathcad 15 or see below.
The range of the variable in your description is not correct.
finally
The second picture could be this if you exchange the two step function as follows:
If i take to hole cycles(2*T) and I would like leave out the first 45° degrees of each? Like in the first picturer Werner posted?.
Do you mean like this?
A slight modification of Werner's program.
Tommi Lauridsen wrote:
Exactly Richard..
Can you explain to me what the different thins in f3(t) means like t<-t*floor NaN?
NaN is a floating point number representation that means Not A Number; it's used where the result is not representable as a floating point number or one of the other special cases (such as infinity). Mathcad's plot component simply doesn't plot NaN values, which is why Richard used it to omit values from the plot. (see footnote)
As for t<-t*floor(t*f). The <- construct is the local assignment operator that Mathcad uses in program. See image below for more information on floor.
Stuart
Note:
One of the reasons Mathcad has the NaN value is to represent numbers that are missing from a data set. For example, consider a machine that records the percentage cloud cover throughout the day. On a nice bright sunny, there will be 0 % cloud cover and when you import the hourly records into Mathcad, then each time index on such a day will have 0 in the coverage column. Now consider what happens if the machine breaks down for a couple of days (eg, through boredom or attention seeking). Mathcad will fill any 'empty' cells in an array with zero, but the days in question may have been cloudy. So rather than use a default value that can affect the statistical analysis, we can use NaN instead of zero to indicate that we didn't have valid data. Mathcad has a number of functions that will allow you work with NaNs; for example, IsNan, markNan, matchNan and filterNan.
Nice sheet, FM.
Here's another option for the periodic case that also doesn't plot the 'missing' points.
Stuart
F.M. wrote:
In real signals (energy or power) used in electronics the zero return is essential. To leave the function floating at a certain instant or in a time interval also periodically in practice is a mistake.
Largely true, but I'm not sure it's always true. Consider, for example, a tri-state video opamp
http://www.ti.com/general/docs/lit/getliterature.tsp?baseLiteratureNumber=snos789&fileType=pdf
Your solution is useful in other cases but not in the representation of signals (voltages and currents) functions of time.
That depends upon what you what you mean by "representation" of signals. It may be clearer from an explanatory point of view to show just the part of the signal that it is active, or it may be desired to distinguish between the on and off states.
Stuart
an Arduino ...
... to create a simple low--frequency DSO
I think you should have capitalized the "L" 
Richard Jackson wrote:
an Arduino ...
... to create a simple low--frequency DSO
I think you should have capitalized the "L"
If I was being that precise, I'd have had to add a "V" in front of it! 
Stuart
By playing with the processor registers, I could do the DAC (with fewer bits) near the top end of the LF band, but I couldn't do much with it due to the overhead of getting the information off the Arduino and into the PC.where Processing attempted to update the screen in (near) real time. I might have a go with a Raspberry Pi B+ or an external DAC sometime when I'm running out of things to do.
Яков Рейзенкинд wrote:
Dear colleagues! You got carried away and forgot about Tommi Lauridsen!
Нет, я не забыл. Но Томми, кажется, забыли о нас! 
Stuart
Яков Рейзенкинд wrote:
Stuart! Thanks for the reply in Russian. I use a translator and is very afraid of being not correctly understood. All the best.
Да, я тоже, Яков. Но я учусь русский язык. Таким образом, некоторые из ошибок все мое!
Stuart
