WEBVTT 00:01.580 --> 00:03.520 Hello and welcome back to the costs. 00:03.530 --> 00:10.220 So in the last session we learned a lot about different data types and now we are continuing to increase 00:10.220 --> 00:13.490 our toolset and get familiar with operators. 00:13.550 --> 00:16.960 So operators allow us to have interactions between objects. 00:16.970 --> 00:23.990 And in this sense we are getting closer to work on real world problems where we have many interactions 00:23.990 --> 00:26.330 and relationships between objects. 00:26.330 --> 00:31.190 In this session we also get familiar with the special data type of billions. 00:31.430 --> 00:34.000 But for now let's start with them. 00:34.030 --> 00:38.320 Arithmetic operators and yeah actually we already know most of them. 00:38.330 --> 00:44.840 And this part here is the smallest the repetition classify we have so you are right about we have a 00:44.840 --> 00:50.330 equals five B equals two and C equals seven. 00:50.420 --> 00:56.760 And we know that began at two integers so A plus B gives a seven. 00:56.800 --> 00:59.240 You can subtract two integers A minus. 00:59.240 --> 01:00.200 Big ifs. 01:00.290 --> 01:06.020 Three you can multiply eight times B gives us 10. 01:06.080 --> 01:09.560 We can divide a divided by B. 01:09.560 --> 01:11.110 Give us 2.5. 01:11.120 --> 01:17.210 So this is a float object and that's another operation called flaw divide. 01:17.240 --> 01:18.670 So it's. 01:18.740 --> 01:24.710 So here we have two to slash all sexually and the fifth run the cell. 01:25.520 --> 01:32.000 So we have a division here and then yeah actually v v rounded down to the next integer in this case 01:32.000 --> 01:34.830 too and we can also have an exponential. 01:34.820 --> 01:43.160 So a to the power of B gives us 25 and that's an operator model law. 01:43.460 --> 01:46.500 Let's run this out here model August. 01:46.610 --> 01:49.890 The remainder of the division a divided by B. 01:49.970 --> 01:58.890 So let's check a divided by being five two divided by two is two and the remainder is one. 01:58.900 --> 02:06.880 All right so let's head to comparison operators and ask before we assign some arrivals and then what 02:06.880 --> 02:15.700 we are doing we are comparing is a equal to B and you have to be careful here it's a double equal sign. 02:15.790 --> 02:24.070 So a single equals sign would actually assign a equals b about a double equal sign checks if A is equal 02:24.070 --> 02:27.100 B and then returns true if is equal B. 02:27.640 --> 02:30.970 And the returns are false if A is not equal B. 02:31.930 --> 02:34.880 So here we have a is 5 B is 2. 02:34.930 --> 02:38.110 So I would expect that we get on false 02:41.410 --> 02:45.860 now next operation a exclamation mark equal B. 02:45.950 --> 02:48.110 So what this operation does. 02:48.110 --> 02:52.800 It actually checks if A is not equal to be so. 02:53.060 --> 02:57.740 Yeah we know here a is not equal to be so it should give us a true. 02:58.250 --> 02:59.890 Then we have the less sine. 02:59.900 --> 03:05.110 So the less sine checks if A is smaller or less than B. 03:05.110 --> 03:14.130 And we would expect the false here and we have the greater than sign and this checks of A is greater 03:14.130 --> 03:21.720 than B I would assume that we get a true and we can also do more complex operations so we can check 03:21.720 --> 03:26.380 if A plus B is less are equal than C. 03:26.460 --> 03:30.360 So A plus B seven C is seven. 03:30.360 --> 03:34.500 So C is less or equal than seven. 03:34.500 --> 03:37.140 That's true. 03:37.160 --> 03:44.600 So now before the operators they give us true or false s as a result of the comparison and true and 03:44.600 --> 03:46.160 false they are both. 03:46.180 --> 03:48.660 Yeah especially the data types called boolean. 03:48.710 --> 03:57.770 And if you check the type of truth it gives us bool for boolean and we can also check about the true 03:57.810 --> 04:05.560 stands numerically far by transforming true into an integer and true all A stands for one and we can 04:05.560 --> 04:10.750 also transform faults into an integer and force always stands for zero. 04:10.960 --> 04:12.420 And we can do it the other way around. 04:12.420 --> 04:21.170 We can transform an integer into a pool object and let's try it with one so this gives us a true. 04:21.170 --> 04:25.920 And also if you transform life into beauty this gives us also a true. 04:26.210 --> 04:27.100 And the rules. 04:27.170 --> 04:29.250 Each integer or float. 04:29.300 --> 04:32.690 That is not equal to zero gives us the true. 04:32.690 --> 04:39.680 If we transform it into a pool soon the only number or integer which gives us the false if we transform 04:39.680 --> 04:43.220 it into pool is zero actually. 04:43.220 --> 04:50.180 And you can also check the mathematical behavior of true and false by applying arithmetic operations 04:50.180 --> 04:54.040 so we can calculate five times true true stands for one. 04:54.050 --> 04:55.490 So we would expect five. 04:55.690 --> 04:57.440 And that's true. 04:57.440 --> 05:03.110 And we can also make an addition so five plus true guess six. 05:03.170 --> 05:09.180 And let's try the same with false or five times false returns zero. 05:09.500 --> 05:14.750 And we can also assign a brilliant object to our rivals so that's known no problem. 05:14.750 --> 05:16.990 So five equals two. 05:16.990 --> 05:26.610 That's false and we assign false to the variety the empty is now stands for False and we can also then 05:26.610 --> 05:28.520 make operations on the. 05:28.530 --> 05:32.400 So five times the D stands for False gives us zero. 05:33.120 --> 05:40.140 So earlier when we learned about lists we learned that in a list we can actually start each data table 05:40.180 --> 05:40.950 object. 05:40.980 --> 05:44.990 Yeah we can think of and this holds also true for a boolean. 05:45.010 --> 05:47.030 We can put a boolean into a list. 05:47.910 --> 05:56.480 So now let's execute the list L so on the list l this a integer 1 2 integers that's a string cat that's 05:56.480 --> 06:02.500 a float object at one point five and that's a boolean object true. 06:02.510 --> 06:06.520 All right so let's go ahead with a logical operators. 06:06.740 --> 06:14.990 So in the first one this and and this is the so-called logical end and was in logical end does it checks 06:15.140 --> 06:23.390 if all conditions are true and only if conditions are true then we get a true or so true and true gifts 06:23.400 --> 06:25.880 less true if both are true. 06:25.940 --> 06:28.700 So that's easy here in that case. 06:28.700 --> 06:35.390 Now it's getting a bit more difficult so we have two conditions five greater than two and seven greater 06:35.390 --> 06:36.650 than two. 06:36.740 --> 06:45.320 So we know both conditions are true then we should get a true here and in most cases the end sign works 06:45.350 --> 06:51.500 in the same way so there are some some minor cases that doesn't work but I don't want to go into detail 06:51.500 --> 06:52.190 here. 06:52.750 --> 06:54.750 So to introduce true. 06:55.270 --> 07:00.150 And also 5 greater than 2 and 7 greater than to give us 2. 07:00.170 --> 07:02.580 So let's go ahead with true and false. 07:02.610 --> 07:08.390 So we only get a true if both statements are true but obviously false is not true. 07:08.390 --> 07:12.420 Now we have 5 greater than 2 and 7 less than 2. 07:12.440 --> 07:18.400 So obviously 7 less than 2 is false and not all conditions are true. 07:18.410 --> 07:25.740 So we should get a false and also false and false will give us a false and five. 07:25.850 --> 07:34.730 Less than two is false and seven less than two is also false so we should get a false okay. 07:34.740 --> 07:42.990 Let's continue with the logical are so logical are checks the statements and it gives us a true if at 07:42.990 --> 07:45.660 least one conditional statement is true. 07:46.260 --> 07:51.180 So if you have true are true that gives us the true costs at least one condition is true. 07:51.180 --> 07:58.630 So yeah both conditions true alternatively you can use the pipe symbol for or so on. 07:58.740 --> 08:04.590 Yeah the very most cases this also works so depends on whether your keyboard is uh American English 08:04.590 --> 08:05.620 or European one. 08:05.710 --> 08:10.890 You can find the pipe symbol and also with the type symbol true or true. 08:10.980 --> 08:21.060 Gives us true and also five greater to or seventh grader to guess as true true or false gives us also 08:21.090 --> 08:31.470 a true because at least one condition is true and this is also the same as 5 greater than 2 are 7 less 08:31.470 --> 08:39.750 to us or 5 greater 2 is a true statement so this gives us true and false and false gives us a false 08:39.780 --> 08:47.480 because no no statement is true here and last but not least we have the not logical operator so the 08:47.500 --> 08:51.420 not logical operator simply reverses true and false. 08:51.420 --> 08:56.480 So if we have actually false and say Not false is true. 08:56.490 --> 09:04.890 So that's quite easy and not true as false and last but not least now we have a bit more complicated 09:04.890 --> 09:05.800 example. 09:05.970 --> 09:18.420 We start here with this bracket 5 greater 2 is true not true is false false or false gives false and 09:18.420 --> 09:23.760 then here outside the record is not so not false should give us true. 09:25.290 --> 09:27.280 So that's it for the upper right us. 09:27.300 --> 09:31.490 And I hope you enjoyed it and you will see us in the next session. 09:31.490 --> 09:35.070 Uh about conditional statements if elif X and Y. 09:35.640 --> 09:37.020 So seen by.