Fortran Programming Tutorials (Revised) : 027 : Trigonometric Identities; Intro to GNUplot Video Lecture | Introduction to Fortran Programming (Basic Level) - Database Management

hi guys my name is Errol and welcome to
my channel this series is a series of
tutorials on Fortran programming now in
the last tutorial we were in the middle
of you know we were in the middle of a
function program where and we were
trying to calculate trigonometric
identities and in that we are using
arrays we are using trigonometric
function trinsic trigonometric functions
and arrays to verify this now the last
part what we did is that we calculated
that the sine sine sine values cosine
values tan cosecant secant and cart and
we just wanted to we just printed how
the how the values of x and y look x and
y looked looked like for all the values
now what I did in this program I just
made some slight modification not a
modification but a slight change what I
did is I did used a new formatting
symbol called me this 15 Mohammed symbol
was already there and it is a new format
called as 10 for Merton in which I
represented the value I represent that I
am representing two numbers f10 f10 come
10.4 and f10 point for with space of
with five spaces between them okay and
then what I'm doing why I opened a new
file called us called a sign X dot txt
and inside while printing them along in
the while printing them on the screen
I'm using I'm writing these values
writing these values to the file okay in
the in the format and then I am adding
this values to the file sign X dot T
using this unit one and with this farm
with the farmer given by a format number
10
alright now once this is this is done
what I'm doing I'm just closing this
file up ok now if I were to you know
compile this again ok see Fortran
I mean build this again T Fortran this
is Drake underscore ID n f9 t - o with
that trig ok click enter
it looks should be fine we get an Alex I
this the ignore this text because I
ignore this text because you know I just
tried this out earlier so I can just
remove this up again sine X dot txt and
then click LS yeah unless the now and I
run this text and this final trick dot
exe it's printing up okay let me this
rises up it's fine
now we just printed up all the values of
the sine of the sine function from zero
all the way till you know all the way
till you know 360 degrees okay well this
also happened let me clear the screen it
generated a sign the sine sine X dot txt
text again okay now I just open use this
with kini I just open this file okay
this and as stated before as shown
earlier in the tutorial he generated the
value for sine X in for all the 100 and
you know 101 points okay now okay now
what do we do I just close this we will
come back we'll come back here and and
what I'm doing right now I'll just add a
few more variables here few more
variables the the same the same category
okay this will be sine 2x cos 2x okay
time to X 2x and then see can see see
can 2x
and then cos secant cosecant 2x 2x and
then okay sine cos tan secant cosecant
cut card 2x okay that being added that
being added what I'm going to do is I'm
going to find the square of this so what
I do is that sine 2x equals sine X power
2 as simple as that now we just if I
just copy this again this is cause this
is cos okay
and now if I just do this again this is
Dan this is Dan again ctrl D yeah cause
he connects
cause he connects control D see connects
C connects control D like control D and
then our X cut
this is cortex okay
now the sign of this is this the sign
you know let's make let's just check the
sign value first before we do it before
we do all this stuff now the sign of
this is this okay you know let's create
another format call us you know another
twenty okay okay I just play this again
twenty okay therefore the sine squared
of this is this and what they do is that
I just copy this again twenty okay and
then I just put sign towards okay now
what now this being this being done what
I'm going to do here
so here I'm just writing the sine of X
will be sine X and here the sine square
of X will be sine cosine square of X
will be sine square of X and that I'm
getting printing it over here since this
is law this will obviously work okay
since this will obviously work I'll just
comment this out since we already tried
and this will you know obviously work
but anyway I'll keep it over here just
so that we can just have a look at it
okay and now what I'm going to do is I'm
going to write this file again in a
different format what I'm going to keep
the overall structure the same what I'm
going to do is then I'm going to write f
10.4 go to save this here with this
format being the same I pass the other
variable sine 2x of I okay
now everything works out fine this
should this should work well okay
LS okay find that extension sure
it saved the execution and building is
fine unless now if I just write drag
okay
the sine squared of 360 degrees is this
and you notice it worked fine because we
don't find any negative and I get any
negative values so this looks fine okay
let me just you know is this a little
bit yeah so that we can go have a bigger
look good look at it it starts here and
we notice all the values are positive
all the values are positive and none of
them are negative so it's sucks it's
successful maybe just list all the files
we have we have this sign X dot txt to
me to ensure that it's got to have a
look at it I said genie and the sine X
dot T HD and voila there you have it now
first first column corresponds to the
value of x degrees second value
corresponds to sine x third value
corresponds to the sine square of X now
now before we go on further okay there
is this nice little plotting tool I like
to show you guys and I like to show you
guys call this guy new plot now this was
not actually my idea this was actually
an idea given by in one of the tutorials
I followed to learn Fortran I'll just
show you guys you know I just passed
this video right now I'll show you the
guy show you the person from source from
which I learned this hold on hold on a
second hey guys welcome back I pause
this video to show the play from
tutorial section from which I learned by
me I'll on my learnings Island C
programming sorry I learned photon
programming up from the basics okay
there's this person called us Alan okay
he gave he relate he released a set of
tutorials under the name excel file here
except for okay and here's a Laura he
doesn't have much of videos but he just
has quite a few number of videos on
and in one of his videos especially this
one and this one and this one he he kind
of introduces to the concept of you know
he kind of ended Oost me to the concept
of the new plot and of how to use the
new plot to give and how to combine the
new plot and Fortran and all to you know
run run plots simultaneously okay and
okay I'll just close this uh I just
minimize this and we'll get back to her
we'll get back to our discussion over
here okay we will be I mean I am just
calm I'm not going to admit directly
that I learned from him and I know I
don't mind saying the source of it
because nobody because I believe that
nobody learns completely on their own
everybody needs a little motivation help
and that person Allen would they gave
that okay the tutorial section then
through this profile texif are okay
through the user profile excel file I'm
really thankful for him because he gave
he gave me a quick shorthand
introduction to Fortran which I'm really
very grateful for not only him there are
many people but he is one of the
instrumental people so I thank him for
that and I kind of learned from him and
and things let's have a look let's use K
new plot to say ki new plot to run this
now I just use a terminal I create a new
terminal instead of having it here okay
I just go to the folder where and we
kept there in Fortran tutorials in that
okay in that our files in trig identity
so CD it's trig identities LS there we
have it now the signs a sign X dot txt
is available now before we go before we
go ahead with that what I what I thought
of doing is that installed a new Fortran
canoe P key new plot GNU plot okay
for most some of you guys might know
what gnew plot is but for those with
also
don't know the new plot is actually a
very simple mod simple program okay
developed developed from developed for
making instantaneously very quick plots
very very very quick plots that goes
hand in hand with compiled languages
like C C++ and Fortran these were
actually made to you know make plotting
easier without the need of any
interpreted languages see the problem
with compiled languages is that they
have very pure very poor parting
plotting features their plotting videos
are really really hard to learn and spy
and I don't know how whether we if there
are any party pieces in Fortran but in
see there are plotting features but
those are really really hard to learn in
which you have to take care of each and
every bit ok
so instead gave a plot which I found
from from Alan and I'm just after little
sir after little Google says I found it
really easy now to install the new plot
what I do is if you are in Ubuntu type
sudo apt-get install ok the k new plot a
GNU plot which every calls and click
enter last for a password
just enter your password and will just
read all the files that are available
link it and for me since I already have
gain new plot just shows that give new
plot is already the latest version if
it's not available what do you have to
do is that whatever do is that it will
just show all the less files that are
available click yes and go on with a
click yes and go on with it and when go
new plot is fine
what are you to check whether it's
installed properly ok what do you do is
that type GNU PLO T key no plot and
click enter now if ich if you get a
certificate or the explanation like this
we get a message like this and you get a
new plot terminal like this a gimp long
command plug
command prompt like this then you are
fine yogi no plot is working perfectly
fine if you don't get it that they have
to run this for Mac users and other
Linux users
installation procedures begin new
plotters more it's all more or less the
same maybe we just have to change that
sudo permissions and you know that
apt-get to young get or some other come
some other relevant command based on Mac
and all in for Windows give me blood
this a little difficult to install is a
little difficult install it's not a
straight I stayed us installing and
Lennox or open to our Mac if you guys
remember my first tutorial first
tutorial the introduction videos I
mentioned that you can use cygwin or
mingw and all to install keno plot you
have to do that
for Windows users to get Agee no plot
installed or there might be a gay new
plot version especially for Windows I
haven't checked it but it's worth the
try now what we do is that what we do is
then we just click exit here okay and
now we let's click LS you're here we
will click the chiquinho plot again
you'll go to this terminal okay now what
we can do is plot plot now sign X dot
txt this I think this has to be in
double quotes if I remember right sign X
dot txt let's see as one this to to okay
that is not required but anyway anyway
you get a nice little plot you got you
got a nice little you got a nice little
plot of sine function don't you make
sure this is perfectly fine you guys can
zoom I mean if you guys can you know
zoom this out the first is the function
is very very nice very very nice me by
the way you can still use any other
plotting languages or programs or
interpret other interpret languages like
MATLAB or Python or other other packages
that's your choice it's your perfectly
your choice and perfectly fine you guys
go ahead with you guys go ahead with it
I'll just closes up okay let me just
three plot that again
I think this is not needed okay this
works right I think we need this Court I
think we need this : here if that's what
I should say okay
okay somehow it's modding somehow for
some reason it is plotting fine okay now
what they do is that set grid command
and then let's see expected it's working
fine now on this if I were to plot cost
function also sorry the other function
also let's see how this turns out to be
sorry I plot this okay unfortunately it
doesn't plot it doesn't plot multiple
multiple values I suppose anyway anyway
let's have a let's have a look at this a
little let's have a look at this so the
function of our objective as of now is
achieved we have a gate we are getting
the sine function call plotted it
perfectly okay now I just close this up
you can do the same thing here thing is
I open this individual terminal because
it's easy to you know easy to process
and all okay
this closes up now our sine function is
perking perfectly fine what I do is that
I just remove this formatting
okay I just remove this formatting I
just what control D and I comment this
out I comment this out and you know I
want this out I'd say this save this and
I will take this out of the equation
sorry control D I will come I will
comment this out because this is working
really fine I'll just remove this off to
print the sign square function yeah okay
I thought I'd make a mistake okay fine
now what I'll do is that is that I'll
run this and again the back slash trade
okay
it works fine I click LS okay the the
sine function shows this stick should be
there genie
if I just type genie and then the sign
text okay now that I have it all of them
are positive values now let's have a
look at look at this in the key no plot
okay now I will open this in here itself
Oh hold on I'll be hold on I'll be back
sorry guys my friend just called okay
anyway coming back let's open the new
plot give me plot and then here let's
type our play let's type this command
let's see how this works and there you
have it perfect
there you have it perfect you have the
sine function you have the sine squared
function properly dealt dealt here okay
now this being said our functions are
our calculations are working fine
our calculations are working fine we can
just exit this out exit this out and
close it okay
now this being said our science function
and square cosine function all these
functions are working fine now I'll stop
this video here
next in the next video I mean I saw this
because it's getting a little bigger
okay the next video
we'll finish this trigonometry stuff and
little of game and will you know will
verify this plot in keno plot by mix and
matching these values and looking seeing
how this you know one by proving this
trigonometric identities in a graphical
manner okay thank you guys for watching
see you guys in the next tutorial
and until then do please do subscribe
please do subscribe and the next
tutorial I'll just let me and I'll just
post a little link on I just post a
little link or so I'll show you a page
where and you can learn a little about
genome Fortran and all thank you guys
for watching