If you are a person who still uses pens to take notes or write anything else on paper then you may find this post interesting. Also, do you think any pen will do or, maybe, selecting a pen is an important step to make? I think a pen that is comfortable, durable and nice is a very important thing to have.
Pens come in a number of types like ballpoint, rollerball and fountain. Also, they can be made from different materials such as plastic, aluminum and even wood. The ink that is used in pens can be water or oil based. In addition, the refill tip can have a different diameter which effects the thickness of the lines you can draw or write.
So far, I had a quite expensive Parker fountain pen and more affordable Parker ballpoint pens. I liked the most Parker ballpoint pens, since they are durable and require no maintenance in comparison to fountain pens. And I’ve used ballpoint pens for more than twenty years now.
Parker Jotter pen I had for a long time
I also like the Frixon clicker series of Pilot pens which are made in Japan and have a renowned Japanese quality. These pens allow you to erase what you’ve written and functionally they are just like pencils, except you don’t need to sharpen them.
Frixon clicker erasable pen
Recently, I’ve been looking for a new comfortable pen and a quick search brought to my attention an interesting and peculiar pen from Japan. It was OHTO GS01-S7 ballpoint pen with an aluminum body and having an oil-based black color ink. What is interesting about this pen is that its body comes in a number of colors, while the ink is always black. This pen feels nice to hold and it looks good. Functionally it resembles Parke Jotter pen, but it looks more engineered, in my opinion, and it feels more comfortable than Jotter. Maybe, it’s due to the fact the OHTO pen is longer than Jotter and has a hexagonal cross-section.
OHTO GS01-S7 with 0.7 mm refill
One unexpected feature of OHTO GS01-S7 is that you can swap its original refill with the Parker Jotter one and visa versa. I’ve found about this while watching a review of the OHTO pen by a Japanese youtuber.
Parker Jotter and OHTO GS01-S7 disassembled, side by side
I very much value quality pens, since they have this surprising capability in them. Especially, since OHTO pen only comes with black refills. So if you want to have a blue ink then you can use Parker’s original blue ink with OHTO pen! Isn’t it nice?
OHTO pen with Parker refill
Also, as I mentioned, you can put OHTO GS01-S7 0.5 or 0.7 mm refill in Parker Jotter if you fancy to. Which can be an interesting twist to do.
Parke Jotter pen with OHTO refill
All in all, OHTO GS01-S7 is a solid pen that have a nice looks and feel. It’s delivering smooth writing experience and is satisfying to click, just like a pop it toy. If you’re look for something new and creative, then this pen is for you.
As you probably have heard by this time ChatGPT a machine learning based chatbot created by OpenAI is very famous. It is based on Generative Pretrained Transformer model, hence, GPT in short. It’s quite successful in various tasks ranging from text summarization, essays generation to questions answering. But did you know that it can also generate working code in various programming languages? If you didn’t then this post will provide you with some ideas to try.
Task at hand
I am a Java developer and recently at work I need to solve a certain task. The task was to sort a list of objects where each object in the list had a date time field. Date time field may look like this: 2023-09-17 20:01:02.23.
For example, in the JSON Crack online tool below you can see how such a list of objects can look like
This task seems quite straightforward when the field is of a Java Date type, but in this case the field was of type String. It means that sorting the objects by this field won’t be correct since the objects will be sorted alphabetically instead of based on date and time. A solution is to convert the String data time field into proper Date type and then to sort the objects.
To summarize what needs to be done is as follows
Iterate over the list of objects and compare objects createdDate field by first converting it from String type to Date type.
Using Java Stream API approach
Java 8 version introduced a powerful Streams API that allows processing of collections in a functional way. For example, it is possible to filter, apply mapping or sorting to a collection in a single line of code using a declarative syntax somewhat similar to SQL. So, accomplishing the task of sorting a list of objects that have a createdDate field of Date type is quite simple and if you google how to do it you’ll find a number of solutions.
For example, this is how it can be done based on the Stack Overflow answer.
The issue was that I wasn’t quite able to find a solution that exactly would solve the issue I had, even though I searched a lot. Then I had an idea. When I played with ChatGPT at OpenAI’s website I also played with code that ChatGPT generated for various languages. So, I went to Microsoft Edge browser and opened Bing Chatbot, powered by GPT-4, and wrote the following
and this is the solution that the Bing chatbot provided
Certainly! Here’s an example of a Java code snippet that sorts a list of objects while converting a string field to date type:
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.Date;
import java.util.List;
public class Main {
public static void main(String[] args) {
List<YourObject> yourList = new ArrayList<>();
// Add objects to yourList
// Sort the list based on the string field "dateString"
Collections.sort(yourList, new Comparator<YourObject>() {
@Override
public int compare(YourObject o1, YourObject o2) {
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
try {
Date date1 = dateFormat.parse(o1.getDateString());
Date date2 = dateFormat.parse(o2.getDateString());
return date1.compareTo(date2);
} catch (ParseException e) {
e.printStackTrace();
}
return 0;
}
});
// Print the sorted list
for (YourObject obj : yourList) {
System.out.println(obj);
}
}
}
class YourObject {
private String dateString;
public String getDateString() {
return dateString;
}
public void setDateString(String dateString) {
this.dateString = dateString;
}
// Add other fields and methods as needed
}
In this example, we have a list of objects of type YourObject that contains a string field called dateString. We want to sort the list based on this field, treating it as a date.
To achieve this, we use the Collections.sort() method and provide a custom Comparator implementation. Inside the compare() method, we parse the dateString of each object into a Date object using a SimpleDateFormat. We then compare the two dates using the compareTo() method and return the result.
Please note that you need to replace YourObject with the actual class name and modify the code according to your specific requirements.
Let me know if you need any further assistance!
If you try the example above in a Java online compiler you’ll see that it works right away. Isn’t it amazing? The only issue that I wanted to have this solution using Java Stream API, so I rephrased what I wanted to get.
Certainly! Here’s an example of a Java code snippet that sorts a list of objects while converting a string field to date type using the Java Stream API:
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Comparator;
import java.util.Date;
import java.util.List;
public class Main {
public static void main(String[] args) {
List<YourObject> yourList = new ArrayList<>();
// Add objects to yourList
// Sort the list based on the string field "dateString" using Java Stream API
yourList.sort(Comparator.comparing(obj -> {
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
try {
Date date = dateFormat.parse(obj.getDateString());
return date;
} catch (ParseException e) {
e.printStackTrace();
}
return null;
}));
// Print the sorted list
yourList.forEach(System.out::println);
}
}
class YourObject {
private String dateString;
public String getDateString() {
return dateString;
}
public void setDateString(String dateString) {
this.dateString = dateString;
}
// Add other fields and methods as needed
}
In this example, we have a list of objects of type YourObject that contains a string field called dateString. We want to sort the list based on this field, treating it as a date.
To achieve this using the Java Stream API, we use the sort() method of the List interface and provide a lambda expression as the comparator. Inside the lambda expression, we parse the dateString of each object into a Date object using a SimpleDateFormat. We then return the parsed date for comparison.
Please note that you need to replace YourObject with the actual class name and modify the code according to your specific requirements.
Let me know if you need any further assistance!
Testing the generated code almost as is in an online Java compiler
Well, that last answer was what I needed. We can take it and check that it can run almost as is in an online Java compiler. I made a couple of small adjustments in the generated code:
I instantiated three objects with dateString populated.
I added these objects to a list and
I adjusted println function to print the dateString field, instead of the object itself.
This is how it looked after running
Below come a full source code if you need it
// Online Java Compiler
// Use this editor to write, compile and run your Java code online
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Comparator;
import java.util.Date;
import java.util.List;
public class Main {
public static void main(String[] args) {
List<YourObject> yourList = new ArrayList<>();
// Add objects to yourList
YourObject obj1 = new YourObject();
obj1.setDateString("2023-09-01");
YourObject obj2 = new YourObject();
obj2.setDateString("2022-07-02");
YourObject obj3 = new YourObject();
obj3.setDateString("2021-08-06");
yourList.add(obj1);
yourList.add(obj2);
yourList.add(obj3);
// Sort the list based on the string field "dateString" using Java Stream API
yourList.sort(Comparator.comparing(obj -> {
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
try {
Date date = dateFormat.parse(obj.getDateString());
return date;
} catch (ParseException e) {
e.printStackTrace();
}
return null;
}));
// Print the sorted list
yourList.forEach((obj -> System.out.println(obj.getDateString())));
}
}
class YourObject {
private String dateString;
public String getDateString() {
return dateString;
}
public void setDateString(String dateString) {
this.dateString = dateString;
}
// Add other fields and methods as needed
}
Blowing your socks off
So there you have it. If you are trying to find a solution for a coding issue you face and you don’t find a good example at Stack Overflow or elsewhere, try using GPT-4 based chatbot, for example, Bing and see how it goes. You can be amazed.
Recently, I went to BASICs and I found it fascinating. It is much more interesting programming paradigm then compiled languages development as C like languages since you can program in BASIC interpreter and in assembly at once and get feedback instantly. Also, 6502 CPU is quite easy to understand and memory mapping of the 6502 is also straightforward and interesting to play with.
The only issue is that I find it tedious to type the code in the Commodore 64 emulator directly. But there is a solution, it is possible to import files in D64, RPG and other formats that the emulator supports. It means that you can write BASIC or assembly code in your favorite editor and then import it.
How can you do it?
To be able to do this it there is a need to convert the text file to a format that is supported by Commodore 64. If you search you’ll be able to find a number of tools that people wrote to do just that. Since I have a PC with Windows 11 so I am using a Windows based tool. This tool is called C64List and it comes in handy to be able to convert BASIC files into text files and vice versa.
Prerequisites
Operating System: Windows
Download and extract C64List tool
(Optional) Review supporting documentation file with a very detailed and helpful
This story begins around 1988-89 when I first saw ZX Spectrum clone based on Zilog Z80 microprocessor. It had Sinclair BASIC and ran off the cassette recorder. This first computer was responsible for the interest in computers that I have ever since.
Fast-forward to nowadays, I continue to be interested in how hardware and software work and watched quite a few reverse engineering videos on YouTube, like Apollo Guidance Computer restoration series on CuriousMarc channel and others. Due to this YT algorithm suggests me similar videos. A couples of days ago it suggested me to watch the 27c3: Reverse Engineering the MOS 6502 CPU video about how 6502 CPU was reverse engineered by peeling layers from the chip, taking photographs and then reconstructing actual transistors from the photos. The talk was given by Michael Steil who extensively contributed to documenting everything there is about MOS 6502 CPU and various types of BASIC it ran. The people who reversed engineered the MOS 6502, Greg James, Brian and Barry Silverman also wrote a JavaScript visualization of the inner workings of the 6502 as it chugs alone.
It turns out that Michael Steil implemented a C based simulation of the MOS 6502 and hooked it up to the Commodore BASIC emulator to see how it worked. And it worked indeed!
In the rest of the post I’ll explain how to run that perfect MOS 6502 CPU simulation that runs Commodore 64 BASIC V2 emulator in WSL2 Ubuntu. So hold on.
Prerequisites
Interest in this topic 🙂
Operating System: Linux or Windows 10 with Windows Subsystem For Linux 2 (WSL2)
Source control software: git (should come preinstalled on WSL) to be able to check out the implementation of the 6502 CPU and BASIC
make tool installed
C compiler like, gcc installed
What to expect?
First I’ll explain how to install WSL2 if you don’t have one.
Then I’ll explain who to clone locally the repository that contains MOS 6502 and BASIC simulators.
Then we’ll build them and run them locally.
I’ll provide references to good resources on the subject.
Let’s begin
Install WSL and Ubuntu
As I mentioned Michael’s implementation requires a Linux distribution to run. So if you have Windows as I do then there is a need to install Windows Subsystem For Linux (aka WSL) to be able to run Ubuntu natively on Windows. The whole installation process is easy and takes a couple of minutes. To know how to do it just follow one of the tutorials below
After this we can build the project using Linux make tool. But since it’s not installed on Ubuntu WSL we need to install it first.
Also, make tool requires C compiler in order to compile the code. So we need to install one of the available C compilers for Linux. We’ll use gcc compiler.
Install make, by running the command below.
sudo apt install make
Next, let’s install gcc compiler. If you’ll be asked Do you want to continue? type Y.
sudo apt install gcc
Now that both of the tools are installed let’s run make command
make
What you’ll see that there will be an error and it has to do with the source code that we cloned
amc@MINE-LAPTOP-130JJTQ6:~/perfect6502$ make
cc -Werror -Wall -O3 -c -o perfect6502.o perfect6502.c
cc -Werror -Wall -O3 -c -o netlist_sim.o netlist_sim.c
netlist_sim.c: In function ‘getGroupValue’:
netlist_sim.c:390:1: error: control reaches end of non-void function [-Werror=return-type]
To fix this issue there is a need to apply Pull Request (PR) one of the users submitted.
To do this run this command
git fetch origin pull/10/head:pr_number10
You’d think that’s it. But you are wrong and there is a need to update Makefile to be able to build the project. To do this we need to comment out the line below in the file
OBJS+=measure.o
Commenting out is done using ‘#’ character as a first one in the line.
I am using vi editor to do this. On WSL it is possible to edit this file even in notepad.
Update Makefile using Windows notepad
When you are in the perfect6502 directory type
explorer.exe .
You should see Windows File Explorer opens
Now, you can select open with notepad and comment out that line in notepad.
Okay, now we are good to run make
amc@MINE-LAPTOP-130JJTQ6:~/perfect6502$ make
cc -Werror -Wall -O3 -c -o perfect6502.o perfect6502.c
cc -Werror -Wall -O3 -c -o netlist_sim.o netlist_sim.c
cc -Werror -Wall -O3 -c -o cbmbasic/cbmbasic.o cbmbasic/cbmbasic.c
cc -Werror -Wall -O3 -c -o cbmbasic/runtime.o cbmbasic/runtime.c
cc -Werror -Wall -O3 -c -o cbmbasic/runtime_init.o cbmbasic/runtime_init.c
cc -Werror -Wall -O3 -c -o cbmbasic/plugin.o cbmbasic/plugin.c
cc -Werror -Wall -O3 -c -o cbmbasic/console.o cbmbasic/console.c
cc -Werror -Wall -O3 -c -o cbmbasic/emu.o cbmbasic/emu.c
cc -o cbmbasic/cbmbasic perfect6502.o netlist_sim.o cbmbasic/cbmbasic.o cbmbasic/runtime.o cbmbasic/runtime_init.o cbmbasic/plugin.o cbmbasic/console.o cbmbasic/emu.o
If you saw similar output then there were no errors and we can finally run the Commodore 64 BASIC emulator on MOS 6502 CPU simulator.
cbmbasic/cbmbasic
And hooray you should see the screen below
What can you do now?
Well, the sky is the limit. Pay attention that since the MOS 6502 simulator simulates real transistors it’s quite slow. Also, there are still some bugs in the Commodore BASIC emulator so not all commands will work as expected. But most will do.
For example, below comes “Hello, world!” program that will print this sentence, and then concatenate two words in one string and print it out.
Pay attention, that BASIC requires upper case for all commands.
Clear screen
PRINT CHR$(147)
Clean memory
NEW
Reset computer (hence emulator)
SYS 64738
List your program so far
LIST
To update particular line there is a need to retype it in this emulator, while in other emulators you can edit them. As you can see on the C64 online emulator
SUMMARY
Well, there you have it you can use your locally running BASIC with pretty good functionality or you can switch to that C64 online emulator which is faster and supports all of the commands.
ScienceAppliedForGood 