Adjust concatenations

Note

The Macro to Python converter is available from Metview version 5.22.0

In Macro the generic concatenation operator is & (ampersand), which can be used for strings, lists, fieldsets and many other built-in types in the same way. Conversion of these operator calls to Python would require run-time information, which the converter does not posses since it does not actually runs the Macro. To overcome this difficulty the calls to & are replaced by calls to Metview’s built in mv.compat.concat() method in the resulting Python script.

Note

mv.compat.concat() is available from Metview Python version 1.16.0

The following table contains some concatenation examples.

Macro code

Generated Python code

# string
c = a & "my_text"

# list
a = nil
a = a & [12]

# vector
v = a & |1,2,3|

# fieldset, geopoints, bufr
f = g1 & g2

# string
c = mv.compat.concat(a, "my_text")

# list
a = []
a = mv.compat.concat(a, 12)

# numpy array
v = mv.compat.concat(a, np.array([1,2,3]))

# fieldset, geopoints, bufr
f = mv.compat.concat(g1, g2)

While this results in a correctly working code it must be only regarded as a temporary solution. Ideally you should check your code and replace all mv.compat.concat() calls with the proper concatenation used for a given type in Python.

The following table can serve you as a guide to properly convert the & operator calls in Macro to Python:

Macro code

Generated Python code

# string
c = a & "my_text"

# list
a = nil
a = a & [12]

# vector
v = a & |1,2,3|

# fieldset, geopoints, bufr
f = g1 & g2

# string
c = a + "my_text"

# list
a = []
a.append(12)

# numpy array
v = np.concatenate(a, np.array([1,2,3]))

# fieldset, geopoints, bufr
f = mv.merge(g1, g2)