Plot: dealing with data available only on weekdays

I want to plot X (date), Y, and Z. Y has an entry for every day but Z has entry only for weekdays (not weekends). Will the code

plot(X,Y)
hold on
plot(X,smooth(Z))

will give us the smooth (that is, no gaps for Z) graphs? What will be the best way to deal with these data?

[dpb]

How do you want to deal with it? Does it make any sense to interpolate for Z? If were market closing values, say, there simply is no data; making something up would be nonsensical.

Filling wit NaN for missing values will automagically not show those values on a plot; if use a datetime for datenum value for X then the time axis will be real time; there isn't a ready-built function in Matlab that will "squish out" weekends if that's the desire.

[alpedhuez]

What are the options?

[dpb]

You have a general purpose programming language in front of you; you can drive it however desired. The problem is to define what it is you really want in order to implement it.

At least a few of the options would be to

1. ignore weekends entirely
2. use real time and plot data where they fall
3. use real time and missing values for weekends
4. use real time and interpolate data for missing values

It all depends on what the data represent and what you want to try to depict...

Answer 1

[per isakson]

I assume

• X and Y have the same length
• Z is shorter than X
• Y and Z hold one value per day
• the length of X is less than 120

Am I right so far?

I would

• depict the values with markers, rather than lines, e.g. Square and Diamond, respectively
• not show anything for Z for weekends

[alpedhuez]

1-3 are correct. X can be potentially much larger than 120.

[per isakson]

• How do you synchronize Z with Y? How do you know which Z-value belong to which weekday?