[ncl-talk] About Relative Humidity

Barry Lynn barry.h.lynn at gmail.com
Fri Sep 29 01:09:08 MDT 2017


Hello:

I've found that searching on Google with NCL "error message" (or keywords)
often brings me to a previous e-mail or note that answers my question.

Just to mention, NCL is case sensitive, which can trip up new users.

Another approach would be to provide the code that actually works to the
list, after your questions have been answered.  I realize that not everyone
feels comfortable with this, but it can make things easier for others who
follow with the same question.

Barry

On Fri, Sep 29, 2017 at 9:43 AM, Marston Johnston <shejo284 at gmail.com>
wrote:

> Hi NCL users,
>
>
>
> I’m a long-time programmer and have learned over the years that asking a
> question in a user forum requires some learning about what to do and what
> not to do. It takes some time to learn the does and don’t when asking a
> question as well as how to formulate a good question that will get a fast
> response from a lot of people.
>
> Just because you have a question doesn’t mean you should ask it here in
> the NCL forum. *Not all questions are questions for NCL*. *NCL is one of
> the best documented programming code out there.* The users and developers
> are some of the best I’ve come across, which is why I try and read/answer
> questions when I can. But lately I’ve seen a series of questions that
> simply require the person to read the error message and/or exercise some
> good programming and debugging practices as well as reading the
> documentation in order to solve their problem. This is a part of
> programming – a part of good programming.
>
>
>
> Below are some tips I borrowed from Stack Overflow on just this topic. I
> would strongly recommend NCL users – especially those new to programming to
> read these tips before posting a question in the future. I’ve done some
> editing to make more NCL specific. I’ve left some links that I think can
> help.
>
>
>
> What topics can I ask about here?
>
> The best NCL questions have a bit of source code in them and meta data of
> the variable with which you are having problems, but if your question
> generally covers…
>
>    - a specific programming problem, or
>    - a software algorithm, or
>    - software tools commonly used by programmers; and is
>    - a practical, answerable problem that is unique to software
>    development
>
>
>
> Please look around to see if your question has been asked before. It’s
> also OK to ask and answer your own question. Questions which are too broad,
> unclear, or incomplete are difficult to answer.
>
> Some questions are still off-topic, even if they fit into one of the
> categories listed above:
>
>    1. Questions *seeking debugging help ("why isn't this code working?")*
>    must include the desired behavior, a specific problem or error and the
>    shortest code necessary to reproduce it in the question itself. Questions
>    without a clear problem statement are not useful to other readers. See: How
>    to create a Minimal, Complete, and Verifiable example
>    <https://stackoverflow.com/help/mcve>.
>    2. Questions about *a problem that can no longer be reproduced or that
>    was caused by a simple typographical error*. While similar questions
>    may be on-topic here, these are often resolved in a manner unlikely to help
>    future readers. This can often be avoided by identifying and closely
>    inspecting the shortest program necessary to reproduce the problem
>    <https://stackoverflow.com/help/mcve> before posting.
>    3. Questions asking for *work help* must include a summary of the work
>    you've done so far to solve the problem, and a description of the
>    difficulty you are having solving it.
>    4. Questions about *general computing hardware and software* are
>    off-topic for NCL unless they directly involve tools used primarily for
>    programming.
>    5. Questions on *professional server, networking, or related
>    infrastructure administration* are off-topic for NCL unless they
>    directly involve programming or programming tools.
>
>
>
>
>
> *How do I ask a good question?*
>
> We’d love to help you. To *improve your chances* of getting an answer,
> here are some tips:
>
> *Search, and research*
>
> ...and keep track of what you find. Even if you don't find a useful answer
> elsewhere on the site, including links to related questions that *haven't*
> helped can help others in understanding how your question is different from
> the rest.
>
> *Write a title that summarizes the specific problem*
>
> The title is the first thing potential answerers will see, and if your
> title isn't interesting, they won't read the rest. So, *make it count:*
>
>    - *Pretend you're talking to a busy colleague* and have to sum up your
>    entire question in one sentence: what details can you include that will
>    help someone identify and solve your problem? Include any error messages,
>    key APIs, or unusual circumstances that make your question different from
>    similar questions already on the site.
>    - *Spelling, grammar and punctuation are important!* Remember, this is
>    the first part of your question others will see - you want to make a good
>    impression. If you're not comfortable writing in English, ask a friend to
>    proof-read it for you.
>    - If you're having trouble summarizing the problem, *write the title
>    last* - sometimes writing the rest of the question first can make it
>    easier to describe the problem.
>
> Examples:
>
>    - *Bad:* NCL Confusion
>    - *Good:* Why does using float instead of int give me different
>    results when all of my inputs are integers?
>
>
>
> *Introduce the problem before you post any code*
>
> In the body of your question, start by expanding on the summary you put in
> the title. Explain how you encountered the problem you're trying to solve,
> and any difficulties that have prevented you from solving it yourself. The
> first paragraph in your question is the second thing most readers will see,
> so make it as engaging and informative as possible.
>
> *Help others reproduce the problem*
>
> Not all questions benefit from including code. But if your problem is
> *with* code you've written, you should include some. But *don't just copy
> in your entire program!* Not only is this likely to get you in trouble if
> you're posting your employer's code, it likely includes a lot of irrelevant
> details that readers will need to ignore when trying to reproduce the
> problem. Here are some guidelines:
>
>    - Include just enough code to allow others to reproduce the problem.
>    For help with this, read How to create a Minimal, Complete, and
>    Verifiable example <https://stackoverflow.com/help/mcve>.
>    - If it is possible to create a live example of the problem that you
>    can *link* to (for example, on http://sqlfiddle.com/ or
>    http://jsbin.com/) then do so - but also include the code in your
>    question itself. Not everyone can access external sites, and the links may
>    break over time.
>
> *Proof-read before posting!*
>
> Now that you're ready to ask your question, take a deep breath and read
> through it from start to finish. Pretend you're seeing it for the first
> time: *does it make sense?* Try reproducing the problem yourself, in a
> fresh environment and make sure you can do so using only the information
> included in your question. Add any details you missed and read through it
> again. Now is a good time to make sure that your title still describes the
> problem!
>
> *Post the question and respond to feedback*
>
> After you post, leave the question open in your browser for a bit, and see
> if anyone comments. If you missed an obvious piece of information, be ready
> to respond by editing your question to include it. If someone posts an
> answer, be ready to try it out and provide feedback!
>
> *Look for help asking for help*
>
> In spite of all your efforts, you may find your questions poorly-received.
> Don't despair! Learning to ask a good question is a worthy pursuit, and not
> one you'll master overnight. Here are some additional resources that you
> may find useful:
>
>    - Writing the perfect question
>    <http://codeblog.jonskeet.uk/2010/08/29/writing-the-perfect-question/>
>    - How to debug small programs
>    <http://ericlippert.com/2014/03/05/how-to-debug-small-programs/>
>    - Meta discussions on asking questions
>    <http://meta.stackexchange.com/questions/tagged/asking-questions>
>    - How to ask questions the smart way
>    <http://www.catb.org/~esr/faqs/smart-questions.html> — long but good
>    advice.
>
>
>
>
>
>
>
> Cheers,
>
> /M
>
>
>
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> Marston S. Ward, PhD
>
> Department of Earth Sciences
>
> University of Gothenburg, Sweden
>
> Email: marston.johnston at gu.se
>
> SkypeID: marston.johnston
>
> Phone: +46-31-7864901 <+46%2031%20786%2049%2001>
>
> Only the fruitful thing is true!
>
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
>
>
>
>
> *From: *isakhar sakhar isakhar <isakhar.inside13 at gmail.com>
> *Date: *Friday, 29 September 2017 at 03:29
> *To: *Dennis Shea <shea at ucar.edu>
> *Cc: *Marston Johnston <shejo284 at gmail.com>, "ncl-talk at ucar.edu" <
> ncl-talk at ucar.edu>
> *Subject: *Re: [ncl-talk] About Relative Humidity
>
>
>
> Dear Mr.Dennis Shea
>
> Thank you very much for reply me.
>
> I want to obtain the result of Relative Humidity in ASCII file base on
> website https://www.ncl.ucar.edu/Document/Functions/Built-in/wrf_rh.shtml
> by using Example 1.
>
>
>
> I already changed the code as you recommend above but still not working.
>
> Best regards,
>
> Soares
>
>
>
> On Fri, Sep 29, 2017 at 10:02 AM, Dennis Shea <shea at ucar.edu> wrote:
>
> You should examine the error message and the line at which it occurs.
>
> RH: [Time | ntim] x [bottom_top | klevel] x [south_north | ny] x
> [west_east | nx]
>
> -----
> You have
>
> do it = 0,ntimes-1
> print (sprintf("%5.2f",it)+""\
>       +sprintf("%19.2f",RH(it(0,:,:,:)))+"")      ; <====== you have
> indexed 'it'
>
> end do
>
> ---
> Change to:
>
> print (sprintf("%5.2f",it)+""\
>       +sprintf("%19.2f",RH(it,:,:,:))
>
> At *each* 'it' you are  printing a 3D array ... point  by point.
>
> I have no idea why you would want to do that
>
>
>
> On Thu, Sep 28, 2017 at 6:50 PM, isakhar sakhar isakhar <
> isakhar.inside13 at gmail.com> wrote:
>
> Hi Mr. Marston
>
> Yes, I have tried many times to solve the problems before send it here. Do
> you have any idea about the code I attached?
>
> Thank you
>
> Soares
>
>
>
> On Tue, Sep 26, 2017 at 3:55 PM, Marston Johnston <shejo284 at gmail.com>
> wrote:
>
> The error message is quite clear. Did you try and address the problem as
> it states?
>
>
>
> fatal:Number of subscripts do not match number of dimensions of
> variable,(4) Subscripts used, (1) Subscripts expected
> fatal:["Execute.c":8640]:Execute: Error occurred at or near line 43 in
> file RH_WRF.ncl
>
>
>
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> Marston S. Ward, PhD
>
> Department of Earth Sciences
>
> University of Gothenburg, Sweden
>
> Email: marston.johnston at gu.se
>
> SkypeID: marston.johnston
>
> Phone: +46-31-7864901 <+46%2031%20786%2049%2001>
>
> Only the fruitful thing is true!
>
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
>
>
>
>
> *From: *ncl-talk <ncl-talk-bounces at ucar.edu> on behalf of isakhar sakhar
> isakhar <isakhar.inside13 at gmail.com>
> *Date: *Tuesday, 26 September 2017 at 07:50
> *To: *<ncl-talk at ucar.edu>
> *Subject: *[ncl-talk] About Relative Humidity
>
>
>
> Dear NCL Team
>
> I am interesting to know Relative Humidity base on website
> https://www.ncl.ucar.edu/Document/Functions/Built-in/wrf_rh.shtml  by
> using Example 1 but it didn't work.
>
>
>
> What is still go wrong with the code. Here I attach the code.
>
>
>
> Best regards,
>
> Soares
>
>
>
>
>
>
> Variable: RH
> Type: float
> Total Size: 419208372 bytes
>             104802093 values
> Number of Dimensions: 4
> Dimensions and sizes:    [Time | 289] x [bottom_top | 37] x [south_north |
> 99] x [west_east | 99]
> Coordinates:
> Number Of Attributes: 2
>   units :    %
>   description :    Relative Humidity
> fatal:Number of subscripts do not match number of dimensions of
> variable,(4) Subscripts used, (1) Subscripts expected
> fatal:["Execute.c":8640]:Execute: Error occurred at or near line 43 in
> file RH_WRF.ncl
>
> _______________________________________________ ncl-talk mailing list
> ncl-talk at ucar.edu List instructions, subscriber options, unsubscribe:
> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>
>
>
>
> _______________________________________________
> ncl-talk mailing list
> ncl-talk at ucar.edu
> List instructions, subscriber options, unsubscribe:
> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>
>
>
>
>
> _______________________________________________
> ncl-talk mailing list
> ncl-talk at ucar.edu
> List instructions, subscriber options, unsubscribe:
> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>
>


-- 
Barry H. Lynn, Ph.D
Senior Lecturer,
The Institute of the Earth Science,
The Hebrew University of Jerusalem,
Givat Ram, Jerusalem 91904, Israel
Tel: 972 547 231 170
Fax: (972)-25662581

C.E.O, Weather It Is, LTD
Weather and Climate Focus
http://weather-it-is.com
Jerusalem, Israel
Local: 02 930 9525
Cell: 054 7 231 170
Int-IS: x972 2 930 9525
US 914 432 3108
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20170929/4bce51d3/attachment.html>


More information about the ncl-talk mailing list