What Interpolate_1d do?

[ShareRingNS]

interpolate_1dappears in the calculation of many functions.
For example, in mpcalc.lifted_index ,
t500, tp500 = interpolate_1d(units.Quantity(500, 'hPa'), pressure, temperature, parcel_profile)
I need to provide a Pressure，does the Pressure here mean the value of 500hpa? Isn't it equivalent to units.Quantity(500, 'hPa')？

[dopplershift]

interpolate_1d interpolates to calculate a value within a set of discrete values. For instance, if you have two temperature values, say 20 degC and 25 degC, given at 1000 hPa and 500 hPa, you could calculate an estimate of the value at 750 hPa using this:

t750 = interpolate_1d(units.Quantity(750, 'hPa'), units.Quantity([1000, 500], 'hPa'), units.Quantity([20, 25], 'degC'))

I should also note that interpolate_1d is only intended for internal use and isn't part of the supported API. It is not guaranteed to exist within the codebase for future use.

[ShareRingNS]

Thanks, so if I already have the required pressure value, I don't need to use this function, right?

[dopplershift]

Well, it's not a public function so you shouldn't be using it at all. 😉 But correct, interpolation isn't necessary when you have the needed levels, we use it in our calculations to ensure we work on more generic datasets.

EDIT: Not sure why I thought interpolate_1d was private, but it's right there publicly in metpy.interpolate.